diff --git a/README.txt b/README.txt
index 08078bf..9e4ad88 100644
--- a/README.txt
+++ b/README.txt
@@ -65,6 +65,10 @@ STANDARD CONFIGURATION:
 
   $ which drush
 
+5. Optional. See top of drush.complete.sh file for instructions adding bash completion for drush
+command to your shell. Once configured, completion works for site aliases, command names,
+shell aliases, global  options, and command-specific options.
+
 
 ADDITIONAL CONFIGURATIONS FOR MAMP:
 -----------------------------------
@@ -83,7 +87,7 @@ If you want to use php 5.3.x, add this line instead
   export PATH="/Applications/MAMP/Library/bin:/Applications/MAMP/bin/php5.3/bin:$PATH"
 
 If you have MAMP v.1.84 or lower, this configuration will work for both version of php:
-  
+
   export PATH="/Applications/MAMP/Library/bin:/Applications/MAMP/bin/php5/bin:$PATH"
 
 Additionally, you may need to adjust your php.ini settings before you can use
@@ -160,12 +164,12 @@ disable_classes are empty.
 
 INSTALLING DRUSH ON WINDOWS:
 ----------------------------
-Windows support is improving, but is still lacking! Consider using on 
+Windows support is improving, but is still lacking! Consider using on
 Linux/Unix/OSX using Virtualbox or other virtual machine.
 
 There is a Windows msi installer for drush available at:
 
-    http://drush.ws/drush_windows_installer.  
+    http://drush.ws/drush_windows_installer.
 
 Please see that page for more information on running Drush on Windows.
 
@@ -261,7 +265,7 @@ COMMANDS
 Drush can be extended to run your own commands. Writing a Drush command is no harder
 than writing simple Drupal modules, since they both follow the same structure.
 
-See sandwich.drush.inc for light details on the internals of a Drush command file.
+See examples/sandwich.drush.inc for light details on the internals of a Drush command file.
 Otherwise, the core commands in Drush are good models for your own commands.
 
 You can put your Drush command file in a number of places:
diff --git a/commands/core/archive.drush.inc b/commands/core/archive.drush.inc
index 7b3465e..cd92d4a 100644
--- a/commands/core/archive.drush.inc
+++ b/commands/core/archive.drush.inc
@@ -98,7 +98,7 @@ function drush_archive_dump($sites_subdirs = '@self') {
   }
   else {
     $first = current($full);
-    $prefix = count($sites_subdirs) > 1 ? 'multiple_sites' : $first['default']['default']['database'];
+    $prefix = count($sites_subdirs) > 1 ? 'multiple_sites' : str_replace('/', '-', $first['databases']['default']['default']['database']);
   }
   $temp_dest_name = "$prefix.$date.tar";
 
@@ -171,7 +171,7 @@ function drush_archive_dump($sites_subdirs = '@self') {
     foreach ($alias['databases'] as $dbkey => $target) {
       // Use a subdirectory name matching the docroot name.
       drush_mkdir("{$tmp}/{$docroot}");
-      $result_file = "{$tmp}/{$target['default']['database']}.sql";
+      $result_file = $tmp . '/' . basename($target['default']['database']) . '.sql';
       $table_selection = drush_sql_get_table_selection();
       list($dump_exec, $dump_file) = drush_sql_build_dump_command($table_selection, $target['default'], $result_file);
       drush_shell_exec($dump_exec);
@@ -207,7 +207,8 @@ function drush_archive_dump($sites_subdirs = '@self') {
     );
     // Add info for each DB connection (usually only 1);
     foreach ($alias['databases'] as $dbkey => $target) {
-      $site["database-$dbkey-file"] = './' . $target['default']['database'] . '.sql';
+      // basename() is for sqlite's sake.
+      $site["database-$dbkey-file"] = './' . basename($target['default']['database'] . '.sql');
       $site["database-$dbkey-driver"] = $target['default']['driver'];
     }
     // The section title is the sites subdirectory name.
diff --git a/commands/core/core.drush.inc b/commands/core/core.drush.inc
index 906ec53..fd47668 100644
--- a/commands/core/core.drush.inc
+++ b/commands/core/core.drush.inc
@@ -189,8 +189,8 @@ function core_drush_command() {
   $items['site-install'] = array(
     'description' => 'Install Drupal along with modules/themes/configuration using the specified install profile.',
     'arguments' => array(
-      'profile' => 'the install profile you wish to run. defaults to \'default\' in D6, \'standard\' in D7',
-      'key=value...' => 'any additional settings you wish to pass to the profile. Only support on D7. The key is in the form [form name].[parameter name].',
+      'profile' => 'the install profile you wish to run. defaults to \'default\' in D6, \'standard\' in D7+',
+      'key=value...' => 'any additional settings you wish to pass to the profile. Only support on D7+. The key is in the form [form name].[parameter name].',
     ),
     'options' => array(
       'db-url' => 'A Drupal 6 style database URL. Only required for initial install - not re-install.',
@@ -209,7 +209,7 @@ function core_drush_command() {
     'examples' => array(
       'drush site-install expert --locale=uk' => '(Re)install using the expert install profile. Set default language to Ukranian.',
       'drush site-install --db-url=mysql://root:pass@localhost:port/dbname' => 'Install using the specified DB params.',
-      'drush site-install --db-url=sqlite:/full/path/to/database.sqlite' => 'Install using SQLite (D7 only).',
+      'drush site-install --db-url=sqlite://sites/example.com/files/.ht.sqlite' => 'Install using SQLite (D7+ only).',
       'drush site-install --account-name=joe --account-pass=mom' => 'Re-install with specified uid1 credentials.',
       'drush site-install standard install_configure_form.site_default_country=FR my_profile_form.my_settings.key=value' => 'Pass additional arguments to the profile (D7 only).',
     ),
@@ -267,9 +267,9 @@ function core_drush_command() {
   $items['batch-process'] = array(
     'description' => 'Process operations in the specified batch set',
     'hidden' => TRUE,
-      'arguments' => array(
-        'batch-id' => 'The batch id that will be processed',
-      ),
+    'arguments' => array(
+      'batch-id' => 'The batch id that will be processed',
+    ),
     'bootstrap' => DRUSH_BOOTSTRAP_DRUPAL_LOGIN,
   );
 
@@ -287,6 +287,21 @@ function core_drush_command() {
     'topic' => TRUE,
     'bootstrap' => DRUSH_BOOTSTRAP_DRUSH,
   );
+  $items['core-quick-drupal'] = array(
+    'description' => 'Download, install, serve and login to Drupal with minimal configuration and dependencies.',
+    'bootstrap' => DRUSH_BOOTSTRAP_DRUSH,
+    'aliases' => array('qd'),
+    'arguments' => array(
+      'site' => 'Short name for the site to be created - used as a directory name and as sqlite file name. Optional - if omitted timestamped "quick-drupal" directory will be used instead.',
+      'projects' => 'A list of projects to download into the new site. If projects contain extensions (modules or themes) with the same name they will be enabled by default. See --enable option to control this behaviour further.',
+    ),
+    'examples' => array(
+      'drush qd --profile=minimal --dev --cache --default-major=8 --yes' => 'Fire up dev release of Drupal site with minimal install profile.',
+      'drush qd testsite devel --server=admin --browser=firefox --cache --yes' => 'Fire up stable release of Drupal site called "testsite" .',
+    ),
+  );
+  // Add in options/engines.
+  drush_core_quick_drupal_options($items);
   return $items;
 }
 
@@ -304,6 +319,19 @@ function core_help_complete() {
  * Command argument complete callback.
  *
  * @return
+ *   Array of available profile names.
+ */
+function core_site_install_complete() {
+  $max = drush_bootstrap_max(DRUSH_BOOTSTRAP_DRUPAL_ROOT);
+  if ($max >= DRUSH_BOOTSTRAP_DRUPAL_ROOT) {
+    return array('values' => array_keys(drush_find_profiles(DRUPAL_ROOT)));
+  }
+}
+
+/**
+ * Command argument complete callback.
+ *
+ * @return
  *  Array of available site aliases.
  */
 function core_core_rsync_complete() {
@@ -671,8 +699,106 @@ function _drush_core_is_named_in_array($key, $the_array) {
 }
 
 /**
+ * Callback for core-quick-drupal command.
+ */
+function drush_core_quick_drupal() {
+  $requests = FALSE;
+  $args = func_get_args();
+  if (empty($args)) {
+    $name = 'quick-drupal-' . gmdate('YmdHis', $_SERVER['REQUEST_TIME']);
+  }
+  else {
+    $name = array_shift($args);
+    if (!empty($args)) {
+      $requests = pm_parse_arguments($args, FALSE);
+    }
+  }
+  $base = getcwd() . '/' . $name;
+  drush_set_option('destination', $base);
+  drush_set_option('backend', TRUE);
+  drush_set_option('drupal-project-rename', 'drupal');
+  if (drush_invoke('pm-download', array(drush_get_option('core', 'drupal'))) === FALSE) {
+    return drush_set_error('QUICK_DRUPAL_CORE_DOWNLOAD_FAIL', 'Drupal core download/extract failed.');
+  }
+  drush_set_option('root', $base . '/drupal');
+  if (!drush_get_option('db-url', FALSE)) {
+    drush_set_option('db-url', 'sqlite:' . $base . '/' . $name . '.sqlite');
+  }
+  if (!drush_bootstrap_to_phase(DRUSH_BOOTSTRAP_DRUPAL_ROOT)) {
+    return drush_set_error('QUICK_DRUPAL_ROOT_LOCATE_FAIL', 'Unable to locate Drupal root directory.');
+  }
+  if ($requests) {
+    // Unset --destination, so that downloads go to the site directories.
+    drush_unset_option('destination');
+    if (drush_invoke('pm-download', $requests) === FALSE) {
+      return drush_set_error('QUICK_DRUPAL_PROJECT_DOWNLOAD_FAIL', 'Project download/extract failed.');
+    }
+  }
+  drush_invoke('site-install');
+  // Log in with the admin user.
+  drush_set_option('user', '1');
+  if (!drush_bootstrap_to_phase(DRUSH_BOOTSTRAP_DRUPAL_LOGIN)) {
+    return drush_set_error('QUICK_DRUPAL_INSTALL_FAIL', 'Drupal core install failed.');
+  }
+  $enable = pm_parse_arguments(drush_get_option('enable', $requests));
+  if (!empty($enable)) {
+    if (drush_invoke('pm-enable', $enable) === FALSE) {
+     return drush_set_error('QUICK_DRUPAL_PROJECT_ENABLE_FAIL', 'Project enable failed.');
+    }
+  }
+  drush_print(dt('Login URL: ') . drush_invoke('user-login'));
+  if ($server = drush_get_option('server', '/')) {
+    drush_invoke('runserver', array($server));
+  }
+}
+
+/**
+ * Include options and engines for core-quick-drupal command, aggregated from
+ * other command options that are available. We prefix option descriptons,
+ * to make the long list more navigable.
+ *
+ * @param $items
+ *   The core commandfile command array, by reference. Used to include
+ *   site-install options and add options and engines for core-quick-drupal.
+ */
+function drush_core_quick_drupal_options(&$items) {
+  $options = array(
+    'core' => 'Drupal core to download. Defaults to "drupal" (latest stable version).',
+    'enable' => 'Specific extensions (modules or themes) to enable. By default, extensions with the same name as requested projects will be enabled automatically.',
+    'server' => 'Host IP address and port number to bind to and path to open in web browser (hyphen to clear a default path), all elements optional. See runserver examples for shorthand.',
+    'no-server' => 'Avoid starting runserver (and browser) for the created Drupal site.',
+    'browser' => 'Optional name of a browser to open site in. If omitted the OS default browser will be used. Set --no-browser to disable.',
+  );
+  $pm = pm_drush_command();
+  foreach ($pm['pm-download']['options'] as $option => $description) {
+    $options[$option] = 'Download option: ' . $description;
+  }
+  // Unset a few options that are not usable here, as we control them ourselves
+  // or they are otherwise implied by the environment.
+  unset($options['destination']);
+  unset($options['drupal-project-rename']);
+  unset($options['default-major']);
+  unset($options['use-site-dir']);
+  foreach ($items['site-install']['options'] as $option => $description) {
+    $options[$option] = 'Site install option: ' . $description;
+  }
+  unset($options['sites-subdir']);
+  $runserver = runserver_drush_command();
+  foreach ($runserver['runserver']['options'] as $option => $description) {
+    $options[$option] = 'Runserver option: ' . $description;
+  }
+  unset($options['user']);
+  $items['core-quick-drupal']['options'] = $options;
+  $items['core-quick-drupal']['engines'] = $pm['pm-download']['engines'];
+}
+
+/**
  * Command callback. Runs "naked" php scripts
  * and drush "shebang" scripts ("#!/usr/bin/env drush").
+ *
+ * @params
+ *   Command arguments, optional. First argument is site name, remaining
+ *   argument(s) are contrib modules to install.
  */
 function drush_core_php_script() {
   $found = FALSE;
diff --git a/commands/core/drupal/batch.inc b/commands/core/drupal/batch.inc
index c7ea875..41dee24 100644
--- a/commands/core/drupal/batch.inc
+++ b/commands/core/drupal/batch.inc
@@ -58,7 +58,8 @@ function _drush_backend_batch_process($command = 'batch-process', $args) {
       else {
         $data = drush_invoke_process('@self', $command, $args, array($batch['id']));
       }
-      $finished = drush_get_error() || !$data || ($data['context']['drush_batch_process_finished'] == TRUE);
+
+      $finished = drush_get_error() || !$data || (isset($data['context']['drush_batch_process_finished']) && $data['context']['drush_batch_process_finished'] == TRUE);
     }
   }
 }
diff --git a/commands/core/drupal/environment.inc b/commands/core/drupal/environment.inc
index b9cbfeb..33dd2ff 100644
--- a/commands/core/drupal/environment.inc
+++ b/commands/core/drupal/environment.inc
@@ -18,6 +18,19 @@ function drush_get_modules() {
 }
 
 /**
+ * Returns drupal required modules, including modules declared as required dynamically.
+ */
+function _drush_drupal_required_modules($module_info) {
+  $required = drupal_required_modules();
+  foreach ($module_info as $name => $module) {
+    if (isset($module->info['required']) && $module->info['required']) {
+      $required[] = $name;
+    }
+  }
+  return array_unique($required);
+}
+
+/**
  * Return dependencies and its status for modules.
  *
  * @param $modules
diff --git a/commands/core/drupal/environment_6.inc b/commands/core/drupal/environment_6.inc
index a8d622f..455f44d 100644
--- a/commands/core/drupal/environment_6.inc
+++ b/commands/core/drupal/environment_6.inc
@@ -26,6 +26,19 @@ function drush_get_modules() {
   return $modules;
 }
 
+/**
+ * Returns drupal required modules, including their dependencies.
+ *
+ * A module may alter other module's .info to set a dependency on it.
+ * See for example http://drupal.org/project/phpass
+ */
+function _drush_drupal_required_modules($module_info) {
+  $required = drupal_required_modules();
+  foreach ($required as $module) {
+    $required = array_merge($required, $module_info[$module]->info['dependencies']);
+  }
+  return $required;
+}
 
 /**
  * Return dependencies and its status for modules.
diff --git a/commands/core/site_install.drush.inc b/commands/core/site_install.drush.inc
index 0ff781d..589b1bb 100644
--- a/commands/core/site_install.drush.inc
+++ b/commands/core/site_install.drush.inc
@@ -23,7 +23,7 @@ function drush_core_pre_site_install() {
   }
   if ($sites_subdir = drush_get_option('sites-subdir')) {
     // Needed so that we later bootstrap into the right site.
-    drush_set_option('uri', 'http://'.$sites_subdir);
+    drush_set_option('uri', 'http://' . $sites_subdir);
   }
   else {
     $sites_subdir = 'default';
diff --git a/commands/core/upgrade.drush.inc b/commands/core/upgrade.drush.inc
index db15309..c29ad08 100644
--- a/commands/core/upgrade.drush.inc
+++ b/commands/core/upgrade.drush.inc
@@ -110,7 +110,7 @@ function drush_upgrade_site_upgrade_check_parameters($target_key = NULL) {
  *
  * This runs bootstrapped to the SOURCE site.
  */
-function drush_upgrade_site_upgrade($target_key) {
+function drush_upgrade_site_upgrade($target_key = NULL) {
   // Presume we are ready to go (n.b. some checks already performed in 'validate')
   $ready_to_upgrade = TRUE;
   $result = TRUE;
diff --git a/commands/core/watchdog.drush.inc b/commands/core/watchdog.drush.inc
index f1da505..48490cc 100644
--- a/commands/core/watchdog.drush.inc
+++ b/commands/core/watchdog.drush.inc
@@ -223,7 +223,10 @@ function core_watchdog_format_result($result, $full = FALSE) {
 
   // Message.
   if (drush_drupal_major_version() >= 6) {
-    $variables = unserialize($result->variables);
+    $variables = $result->variables;
+    if (is_string($variables)) {
+      $variables = unserialize();
+    }
     if (is_array($variables)) {
       $result->message = strtr($result->message, $variables);
     }
diff --git a/commands/pm/download.pm.inc b/commands/pm/download.pm.inc
index 218ffd8..a94ab9b 100644
--- a/commands/pm/download.pm.inc
+++ b/commands/pm/download.pm.inc
@@ -31,25 +31,25 @@ function drush_pm_download_validate() {
   // Validate --variant or enforce a sane default.
   $variant = drush_get_option('variant', FALSE);
   if ($variant) {
-    if (!in_array($variant, array('core', 'no-core', 'make'))) {
+    if (!in_array($variant, array('full', 'projects', 'profile-only'))) {
       drush_log(dt('Unknown variant !variant. Valid values: !variations', array('!variant' => $variant, '!variations' => implode(', ', $variations))), 'error');
     }
   }
-  // core and no-core variants are only valid for wget package handler.
+  // full and projects variants are only valid for wget package handler.
   $package_handler = drush_get_option('package-handler', 'wget');
-  if (($package_handler != 'wget') && ($variant != 'make')) {
-    $new_variant = 'make';
+  if (($package_handler != 'wget') && ($variant != 'profile-only')) {
+    $new_variant = 'profile-only';
     if ($variant) {
       drush_log(dt('Variant !variant is incompatible with !ph package-handler.', array('!variant' => $variant, '!ph' => $package_handler)), 'warning');
     }
   }
-  // If we are working on a drupal root, core variant is not an option.
+  // If we are working on a drupal root, full variant is not an option.
   else if (drush_get_context('DRUSH_BOOTSTRAP_PHASE') >= DRUSH_BOOTSTRAP_DRUPAL_ROOT) {
-    if ((!$variant) || (($variant == 'core') && (!isset($new_variant)))) {
-      $new_variant = 'no-core';
+    if ((!$variant) || (($variant == 'full') && (!isset($new_variant)))) {
+      $new_variant = 'projects';
     }
-    if ($variant == 'core') {
-      drush_log(dt('Variant core is not a valid option within a Drupal root.'), 'warning');
+    if ($variant == 'full') {
+      drush_log(dt('Variant full is not a valid option within a Drupal root.'), 'warning');
     }
   }
 
@@ -463,4 +463,3 @@ function _pm_download_destination($type) {
 
   return $destination;
 }
-
diff --git a/commands/pm/package_handler/git_drupalorg.inc b/commands/pm/package_handler/git_drupalorg.inc
index fe933e8..60d19cf 100644
--- a/commands/pm/package_handler/git_drupalorg.inc
+++ b/commands/pm/package_handler/git_drupalorg.inc
@@ -51,16 +51,32 @@ function package_handler_download_project(&$request, $release) {
   $request['repository'] = $repository;
   $tag = $release['tag'];
 
-  if (drush_get_option('cache')) {
-    $gitcache = drush_server_home() . '/.drush/gitcache';
-    drush_gitcache_check($gitcache);
-
-    drush_shell_cd_and_exec($gitcache, 'git remote show');
-    $cached_modules = drush_shell_exec_output();
-
-    if (!in_array($request['name'], $cached_modules)) {
-      drush_gitcache_add_project($gitcache, $request, $repository);
+  // If the --cache option was given, create a new git reference cache of the
+  // remote repository, or update the existing cache to fetch recent changes.
+  if (drush_get_option('cache') && ($cachedir = drush_directory_cache())) {
+    $gitcache = $cachedir . '/git';
+    $projectcache = $gitcache . '/' . $request['name'] . '.git';
+    drush_mkdir($gitcache);
+    // Setup a new cache, if we don't have this project yet.
+    if (!file_exists($projectcache)) {
+      // --mirror works similar to --bare, but retrieves all tags, local
+      // branches, remote branches, and any other refs (notes, stashes, etc).
+      // @see http://stackoverflow.com/questions/3959924
+      $command = 'git clone --mirror';
+      if (drush_get_context('DRUSH_VERBOSE')) {
+        $command .= ' --verbose --progress';
+      }
+      $command .= ' %s %s';
+      drush_shell_cd_and_exec($gitcache, $command, $repository, $request['name'] . '.git');
+    }
+    // If we already have this project, update it to speed up subsequent clones.
+    else {
+      // A --mirror clone is fully synchronized with `git remote update` instead
+      // of `git fetch --all`.
+      // @see http://stackoverflow.com/questions/6150188
+      drush_shell_cd_and_exec($projectcache, 'git remote update');
     }
+    $gitcache = $projectcache;
   }
 
   // Clone the repo into its appropriate target location.
@@ -181,46 +197,3 @@ function package_handler_post_download($project) {
   }
 }
 
-/**
- * Check for gitcache directory or create it.
- *
- * @param $gitcache
- *   The location of the gitcache directory.
- */
-function drush_gitcache_check($gitcache) {
-  if (is_dir(drush_server_home() . '/.drush')) {
-    drush_mkdir($gitcache);
-    if (!drush_shell_cd_and_exec($gitcache, 'test $(git rev-parse --is-bare-repository) == "true"')) {
-      drush_shell_cd_and_exec($gitcache, 'git init --bare');
-      drush_shell_cd_and_exec($gitcache, 'git config core.compression 1');
-    }
-  }
-}
-
-/**
- * Add a project to the cache.
- *
- * @param $gitcache
- *   The location of the gitcache directory.
- * @param $request
- *   The project array with name, base and full (final) paths.
- * @param $release
- *   The release details array from drupal.org.
- */
-function drush_gitcache_add_project($gitcache, $request, $repository) {
-  // On the first fetch, git will check for common commits with the remote
-  // repository, so to speed this up we initially fetch from a local clone.
-  $tmpdir = drush_tempdir();
-  $command = 'git clone --bare ';
-  if (drush_get_context('DRUSH_VERBOSE')) {
-    $command .= ' --verbose --progress ';
-  }
-  $command .= '%s';
-  if (drush_shell_cd_and_exec($tmpdir, $command, $repository)) {
-    // Temporarily set the remote url to our temporary clone and fetch from there.
-    drush_shell_cd_and_exec($gitcache, 'git remote add %s %s && git fetch %s --tags', $request['name'], $tmpdir, $request['name']);
-
-    // Change the remote URL and fetch normally.
-    drush_shell_cd_and_exec($gitcache, 'git remote set-url %s %s && git fetch %s --tags', $request['name'], $repository, $request['name']);
-  }
-}
diff --git a/commands/pm/package_handler/wget.inc b/commands/pm/package_handler/wget.inc
index e3a8da5..393405c 100644
--- a/commands/pm/package_handler/wget.inc
+++ b/commands/pm/package_handler/wget.inc
@@ -33,7 +33,7 @@ function package_handler_validate() {
  * @param $release The release details array from drupal.org.
  */
 function package_handler_download_project(&$request, $release) {
-  // Install profiles come in 3 variants. User may specify which one she wants.
+  // Install profiles come in several variants. User may specify which one she wants.
   if ($request['project_type'] == 'profile') {
     // @todo Use xpath to get the right file url.
     $files = $release['files'];
diff --git a/commands/pm/pm.drush.inc b/commands/pm/pm.drush.inc
index 2a02d7f..715d86d 100644
--- a/commands/pm/pm.drush.inc
+++ b/commands/pm/pm.drush.inc
@@ -485,6 +485,21 @@ function drush_get_projects(&$extensions = NULL) {
 }
 
 /**
+ * Returns a list of enabled modules.
+ *
+ * This is a simplified version of module_list().
+ */
+function pm_module_list() {
+  $enabled = array();
+  $rsc = drush_db_select('system', 'name', 'type=:type AND status=:status', array(':type' => 'module', ':status' => 1));
+  while ($row = drush_db_result($rsc)) {
+    $enabled[$row] = $row;
+  }
+
+  return $enabled;
+}
+
+/**
  * @} End of "defgroup extensions".
  */
 
@@ -643,10 +658,11 @@ function drush_pm_enable() {
 
   $args = pm_parse_arguments(func_get_args());
 
+  $extension_info = drush_get_extensions();
+
   $recheck = TRUE;
   while ($recheck) {
     $recheck = FALSE;
-    $extension_info = drush_get_extensions();
 
     // Classify $args in themes, modules or unknown.
     $modules = array();
@@ -729,9 +745,7 @@ function drush_pm_enable() {
     if (!$dependencies_ok) {
       return FALSE;
     }
-    $enabled = array_keys(array_filter(drush_get_modules(), 'pm_is_enabled'));
-    $modules = array_diff(array_merge($modules, $all_dependencies), $enabled);
-
+    $modules = array_diff(array_merge($modules, $all_dependencies), pm_module_list());
     // Discard modules which doesn't meet requirements.
     require_once drush_get_context('DRUSH_DRUPAL_ROOT') . '/includes/install.inc';
     foreach ($modules as $key => $module) {
@@ -766,10 +780,7 @@ function drush_pm_enable() {
   // Enable modules and pass dependency validation in form submit.
   if (!empty($modules)) {
     drush_module_enable($modules);
-    $current = drupal_map_assoc($enabled, 'pm_true');
-    $processed = drupal_map_assoc($modules, 'pm_true');
-    $active_modules = array_merge($current, $processed);
-    drush_system_modules_form_submit($active_modules);
+    drush_system_modules_form_submit(pm_module_list());
   }
 
   // Inform the user of final status.
@@ -841,14 +852,12 @@ function drush_pm_disable() {
 
   if (!empty($modules)) {
     // Add enabled dependents to the list of modules to disable.
-    $enabled = array_keys(array_filter(drush_get_modules(), 'pm_is_enabled'));
     $dependents = drush_module_dependents($modules, $extension_info);
-    $dependents = array_unique($dependents);
-    $dependents = array_intersect($dependents, $enabled);
+    $dependents = array_intersect($dependents, pm_module_list());
     $modules = array_merge($modules, $dependents);
 
     // Discard required modules.
-    $required = drupal_required_modules();
+    $required = drush_drupal_required_modules($extension_info);
     foreach ($required as $module) {
       if (isset($modules[$module])) {
         unset($modules[$module]);
@@ -880,9 +889,7 @@ function drush_pm_disable() {
   // Disable modules and pass dependency validation in form submit.
   if (!empty($modules)) {
     drush_module_disable($modules);
-    $active_modules = array_diff($enabled, $modules);
-    $active_modules = drupal_map_assoc($active_modules, 'pm_true');
-    drush_system_modules_form_submit($active_modules);
+    drush_system_modules_form_submit(pm_module_list());
   }
 
   // Inform the user of final status.
@@ -939,6 +946,7 @@ function drush_pm_uninstall() {
 
   drush_include_engine('drupal', 'environment');
   $module_info = drush_get_modules();
+  $required = drush_drupal_required_modules($module_info);
 
   // Discards modules which are enabled, not found or already uninstalled.
   foreach ($modules as $key => $module) {
@@ -960,7 +968,7 @@ function drush_pm_uninstall() {
     else {
       $dependents = array();
       foreach (drush_module_dependents(array($module), $module_info) as $dependent) {
-        if ($module_info[$dependent]->schema_version != -1) {
+        if (!in_array($dependent, $required) && ($module_info[$dependent]->schema_version != -1)) {
           $dependents[] = $dependent;
         }
       }
@@ -992,23 +1000,6 @@ function drush_pm_uninstall() {
 }
 
 /**
- * Array filter callback to return enabled modules.
- *
- * @param $module
- *  A module object as returned by drush_get_modules().
- */
-function pm_is_enabled($module) {
-  return $module->status;
-}
-
-/**
- * Callback helper.
- */
-function pm_true() {
-  return TRUE;
-}
-
-/**
  * Completes projects' update data with the path to install location on disk.
  *
  * Given an array of release info for available projects, find the path to the install location.
@@ -1532,7 +1523,7 @@ function drush_pm_updatecode_postupdate() {
   drupal_load_updates();
 
   // @see system_requirements().
-  foreach (module_list() as $module) {
+  foreach (pm_module_list() as $module) {
     $updates = drupal_get_schema_versions($module);
     if ($updates !== FALSE) {
       $default = drupal_get_installed_schema_version($module);
@@ -1969,7 +1960,7 @@ function drush_pm_extensions_in_project($project) {
     }
     // Special case: find profiles for drupal < 7.x (no .info)
     if ($project['drupal_version'][0] < 7) {
-      foreach (drush_scan_directory($project['project_install_location'], "/.*\.profile$/", $nomask) as $filename => $info) {
+      foreach (drush_find_profiles($project['project_install_location']) as $filename => $info) {
         $found['profile'][] = $info->name;
       }
     }
diff --git a/commands/pm/updatecode.pm.inc b/commands/pm/updatecode.pm.inc
index b464274..97a5d4c 100644
--- a/commands/pm/updatecode.pm.inc
+++ b/commands/pm/updatecode.pm.inc
@@ -97,7 +97,7 @@ function drush_pm_updatecode() {
       else {
         $update_info[$name]['status'] = DRUSH_PM_REQUESTED_UPDATE;
       }
-      // Set the candidate version to the requested release
+      // Set the candidate version to the requested release.
       $update_info[$name]['candidate_version'] = $release['version'];
     }
   }
@@ -105,7 +105,8 @@ function drush_pm_updatecode() {
   // Table headers.
   $rows[] = array(dt('Name'), dt('Installed version'), dt('Proposed version'), dt('Status'));
 
-  // Process releases, notifying user of status and building a list of proposed updates
+  // Process releases, notifying user of status and
+  // building a list of proposed updates.
   $updateable = pm_project_filter($update_info, $rows, $security_only);
 
   // Pipe preparation.
@@ -118,7 +119,7 @@ function drush_pm_updatecode() {
       $pipe .= str_replace(' ', '-', pm_update_filter($project)). "\n";
     }
     drush_print_pipe($pipe);
-    // Automatically curtail update process if in pipe mode
+    // Automatically curtail update process if in pipe mode.
     $updateable = array();
   }
 
@@ -137,7 +138,8 @@ function drush_pm_updatecode() {
   drush_print($contents);
   drush_print();
 
-  // If specific project updates were requested then remove releases for all others
+  // If specific project updates were requested then remove releases for all
+  // others.
   if (!empty($requests)) {
     foreach ($updateable as $name => $project) {
       if (!isset($requests[$name])) {
@@ -146,7 +148,13 @@ function drush_pm_updatecode() {
     }
   }
 
-  // If there are any locked projects that were not requested, then remove them
+  // Prevent update of core if --no-core was specified.
+  if (isset($updateable['drupal']) && drush_get_option('no-core', FALSE)) {
+    unset($updateable['drupal']);
+    drush_print(dt('Skipping core update (--no-core specified).'));
+  }
+
+  // If there are any locked projects that were not requested, then remove them.
   if (!empty($locked_list)) {
     foreach ($updateable as $name => $project) {
       if ((isset($locked_list[$name])) && (!isset($requests[$name]))) {
@@ -161,7 +169,7 @@ function drush_pm_updatecode() {
     $drush_update_available = drush_check_self_update();
   }
 
-  // Do no updates in simulated mode
+  // Do no updates in simulated mode.
   if (drush_get_context('DRUSH_SIMULATE')) {
     return drush_log(dt('No action taken in simulated mode.'), 'ok');
     return TRUE;
@@ -188,12 +196,7 @@ function drush_pm_updatecode() {
       else {
         drush_print(dt("NOTE: A code update for the Drupal core is available."));
       }
-      if (drush_get_option('no-core', FALSE)) {
-        drush_print(dt('Skipping core update (--no-core specified).'));
-      }
-      else {
-        drush_print(dt("Drupal core will be updated after all of the non-core modules are updated.\n"));
-      }
+      drush_print(dt("Drupal core will be updated after all of the non-core modules are updated.\n"));
     }
   }
 
@@ -218,7 +221,7 @@ function drush_pm_updatecode() {
   }
 
   // After projects are updated we can update core.
-  if ($core_update_available && !drush_get_option('no-core', FALSE)) {
+  if ($core_update_available) {
     drush_print();
     return _pm_update_core($drupal_project, $tmpfile);
   }
diff --git a/commands/runserver/runserver-drupal.inc b/commands/runserver/runserver-drupal.inc
index a4ca965..d860580 100644
--- a/commands/runserver/runserver-drupal.inc
+++ b/commands/runserver/runserver-drupal.inc
@@ -10,12 +10,14 @@
  * Extends the HTTPServer class, handling request routing and environment.
  */
 class DrupalServer extends HTTPServer {
-  public $http_host;
+  // We pass in variables, rather than querying options here, to allow this to
+  // potentially be used in other commands.
+  public $site, $path, $conf_inject, $user, $watchdog, $debug, $first_request_complete;
 
   /**
    * This is the equivalent of .htaccess, passing requests to files if they
    * exist, and all other requests to index.php. We also set a number
-   * of CGI environment variables here.  
+   * of CGI environment variables here.
    */
   function route_request($request) {
     $cgi_env = array();
@@ -23,16 +25,24 @@ class DrupalServer extends HTTPServer {
     // We pass in the effective base_url to our auto_prepend_script via the cgi
     // environment. This allows Drupal to generate working URLs to this http
     // server, whilst finding the correct multisite from the HTTP_HOST header.
-    $cgi_env['RUNSERVER_BASE_URL'] = 'http://localhost:' . $this->port;
+    $cgi_env['RUNSERVER_BASE_URL'] = 'http://' . $this->addr . ':' . $this->port;
 
     // We pass in an array of $conf overrides using the same approach.
     // By default we set drupal_http_request_fails to FALSE, as the httpserver
-    // is unable to process simultanious requests on some systems.
+    // is unable to process simultaneous requests on some systems.
     // This is available as an option for developers to pass in their own
     // favorite $conf overrides (e.g. disabling css aggregation).
-    $conf_inject = drush_get_option('conf-inject', array('drupal_http_request_fails' => FALSE));
+    $conf_inject = $this->conf_inject;
     $cgi_env['RUNSERVER_CONF'] = urlencode(serialize($conf_inject));
 
+    // We pass in the specified user (if set) - should be a fully loaded user
+    // object. This will automatically log this user in the browser during the
+    // first request (but not subsequent requests, to allow logging out).
+    if (!empty($this->user) && $this->user->uid && $this->first_request_complete !== TRUE) {
+      $this->first_request_complete = TRUE;
+      $cgi_env['RUNSERVER_USER'] = urlencode(serialize($this->user));
+    }
+
     // Handle static files and php scripts accessed directly
     $uri = $request->uri;
     $doc_root = DRUPAL_ROOT;
@@ -53,8 +63,38 @@ class DrupalServer extends HTTPServer {
     }
 
     $cgi_env['SCRIPT_NAME'] = '/index.php';
-    $cgi_env['HTTP_HOST'] = $cgi_env['SERVER_NAME'] = $this->http_host;
+    $cgi_env['HTTP_HOST'] = $cgi_env['SERVER_NAME'] = $this->site;
 
     return $this->get_php_response($request, $doc_root . '/index.php', $cgi_env);
   }
+
+  /**
+   * Override get started event.
+   */
+  function listening() {
+    drush_print(dt('HTTP server listening on !addr, port !port (see http://!hostname:!port/), serving site !site...', array('!addr' => $this->addr, '!hostname' => $this->hostname, '!port' => $this->port, '!site' => $this->site)));
+    if (!empty($this->path)) {
+      drush_start_browser($this->path);
+    }
+  }
+
+  /**
+   * Override request done event.
+   */
+  function request_done($request) {
+    drush_print(trim($this->get_log_line($request), "\n"));
+    $headers = $request->response->headers;
+    if ($this->watchdog && isset($headers['X-Runserver-Watchdog'])) {
+      $results = unserialize(urldecode($headers['X-Runserver-Watchdog']));
+      foreach ($results as $result) {
+        $result = (object)$result;
+        $result->uid = $result->user->uid;
+        $result = core_watchdog_format_result($result, TRUE);
+        drush_print("Watchdog: {$result->date} ({$result->severity}, {$result->type}, {$result->user->name}) {$result->message}", 2);
+      }
+    }
+    if ($this->debug) {
+      drush_print_r($request);
+    }
+  }
 }
diff --git a/commands/runserver/runserver-prepend.php b/commands/runserver/runserver-prepend.php
index 8f89d94..15a835c 100644
--- a/commands/runserver/runserver-prepend.php
+++ b/commands/runserver/runserver-prepend.php
@@ -1,29 +1,51 @@
 <?php
-/**
- * @file
- * This file is included using the php "auto_prepend_file" option whenever
- * Drupal is used with runserver.
- * We use this to inject some specific changes so Drupal works correctly in
- * this environment.
- */
 
 // We set the base_url so that Drupal generates correct URLs for runserver
-// (e.g. http://localhost:8888/...), but can still select and serve a specific
+// (e.g. http://127.0.0.1:8888/...), but can still select and serve a specific
 // site in a multisite configuration (e.g. http://mysite.com/...).
 $base_url = $_SERVER['RUNSERVER_BASE_URL'];
 
-/**
- * Configuration added here will apply to all sites.
- * This can be a useful place to apply generic development settings.
- * We hijack system_boot (which core system module does not implement) as
- * a convenient place to inject values into the $conf array.
- */
+// We hijack system_boot (which core system module does not implement) as
+// a convenient place to affect mid-bootstrap changes.
 if (!function_exists('system_boot')) {
   // Check function_exists as a safety net in case it is added in future.
   function system_boot() {
-    global $conf;
+    global $conf, $user;
+    // Inject values into the $conf array - will apply to all sites.
+    // This can be a useful place to apply generic development settings.
     $conf_inject = unserialize(urldecode($_SERVER['RUNSERVER_CONF']));
     // Merge in the injected conf, overriding existing items.
     $conf = array_merge($conf, $conf_inject);
+    if (isset($_SERVER['RUNSERVER_USER'])) {
+      // If a user was provided, log in as this user.
+      $user = unserialize(urldecode($_SERVER['RUNSERVER_USER']));
+      if (function_exists('drupal_session_regenerate')) {
+        // Drupal 7
+        drupal_session_regenerate();
+      }
+      else {
+        // Drupal 6
+        sess_regenerate();
+      }
+    }
   }
-}
\ No newline at end of file
+}
+
+// We hijack system_watchdog (which core system module does not implement) as
+// a convenient place to capture logs.
+if (!function_exists('system_watchdog')) {
+  // Check function_exists as a safety net in case it is added in future.
+  function system_watchdog($log_entry = array()) {
+    static $logs = array();
+    $logs[] = $log_entry;
+    $data = urlencode(serialize($logs));
+    if (function_exists('drupal_add_http_header')) {
+      // Drupal 7
+      drupal_add_http_header('X-Runserver-Watchdog', $data);
+    }
+    else {
+      // Drupal 6
+      drupal_set_header('X-Runserver-Watchdog: ' . $data);
+    }
+  }
+}
diff --git a/commands/runserver/runserver.drush.inc b/commands/runserver/runserver.drush.inc
index 473f831..c5381f1 100644
--- a/commands/runserver/runserver.drush.inc
+++ b/commands/runserver/runserver.drush.inc
@@ -49,13 +49,25 @@ function runserver_drush_command() {
     'description' => 'Runs a lightweight built in http server for development.',
     'bootstrap' => DRUSH_BOOTSTRAP_DRUPAL_SITE,
     'arguments' => array(
-      'addr:port' => 'Host IP address and port number to bind to (default 127.0.0.1:8888). The IP is optional, in which case just pass in the numeric port.',
+      'addr:port/path' => 'Host IP address and port number to bind to and path to open in web browser. Format is addr:port/path, default 127.0.0.1:8888, all elements optional. See examples for shorthand.',
     ),
     'options' => array(
       'php-cgi' => 'Name of the php-cgi binary. If it is not on your current $PATH you should include the full path. You can include command line parameters to pass into php-cgi.',
       'conf-inject' => 'Key-value array of variables to override in the $conf array for the running site. By default disables drupal_http_request_fails to avoid errors on Windows (which supports only one connection at a time). Note that as this is a key-value array, it can only be specified in a drushrc or alias file, and not on the command line.',
+      'default-server' => 'A default addr:port/path to use for any values not specified as an argument.',
+      'user' => 'If opening a web browser, automatically log in as this user (user ID or username)',
+      'watchdog' => 'Collect and integrate watchdog messages from each request into the log',
+      'dns' => 'Resolve hostnames/IPs using DNS/rDNS (if possible) to determine binding IPs and/or human friendly hostnames for URLs and browser.',
     ),
     'aliases' => array('rs'),
+    'examples' => array(
+      'drush rs 8080' => 'Start runserver on 127.0.0.1, port 8080.',
+      'drush rs 10.0.0.28:80' => 'Start runserver on 10.0.0.28, port 80.',
+      'drush rs --php-cgi=php5-cgi --dns localhost:8888/user' => 'Start runserver on localhost (using rDNS to determine binding IP), port 8888, and open /user in browser. Use "php5-cgi" as the php-cgi binary.',
+      'drush rs /' => 'Start runserver on default IP/port (127.0.0.1, port 8888), and open / in browser.',
+      'drush rs --default-server=127.0.0.1:8080/ -' => 'Use a default (would be specified in your drushrc) that starts runserver on port 8080, and opens a browser to the front page. Set path to a single hyphen path in argument to prevent opening browser for this session.',
+      'drush rs --watchdog :9000/admin' => 'Start runserver on 127.0.0.1, port 9000, and open /admin in browser, including any watchdog messages for the session in the log. Note that you need a colon when you specify port and path, but no IP.',
+    ),
   );
   return $items;
 }
@@ -75,7 +87,9 @@ function drush_core_runserver_validate() {
 /**
  * Callback for runserver command.
  */
-function drush_core_runserver($addrport = '8888') {
+function drush_core_runserver($uri = NULL) {
+  global $user;
+
   // Fetch httpserver to our /lib directory, if needed.
   $lib = drush_get_option('lib', DRUSH_BASE_PATH . '/lib');
   $httpserverfile = $lib . '/' . DRUSH_HTTPSERVER_DIR_BASE . substr(DRUSH_HTTPSERVER_VERSION, 0, 7) . '/httpserver.php';
@@ -91,30 +105,95 @@ function drush_core_runserver($addrport = '8888') {
   // Include the library and our class that extends it.
   require_once $httpserverfile;
   require_once 'runserver-drupal.inc';
-  
-  // Determine configuration.
-  if (is_numeric($addrport)) {
-    $addr = '127.0.0.1';
-    $port = $addrport;
+
+  // We pass in the currently logged in user (if set via the --user option),
+  // which will automatically log this user in the browser during the first
+  // request.
+  if (drush_get_option('user', FALSE)) {
+    drush_bootstrap_max(DRUSH_BOOTSTRAP_DRUPAL_LOGIN);
+  }
+
+  // Determine active configuration.
+  $drush_default = array(
+    'host' => '127.0.0.1',
+    'port' => '8888',
+    'path' => '',
+  );
+  $user_default = runserver_parse_uri(drush_get_option('default-server', '127.0.0.1:8888'));
+  $uri = runserver_parse_uri($uri) + $user_default + $drush_default;
+  if (ltrim($uri['path'], '/') == '-') {
+    // Allow a path of a single hyphen to clear a default path.
+    $uri['path'] = '';
   }
-  else {
-    $addrport = explode(':', $addrport);
-    if (count($addrport) !== 2 && is_numeric($addrport[1])) {
-      return drush_set_error('RUNSERVER_INVALID_ADDRPORT', dt('Invalid address/port argument - should be either numeric (port only), or in the "host:port" format..'));
+
+  // Determine and set the new URI.
+  $hostname = $addr = $uri['host'];
+  if (drush_get_option('dns', FALSE)) {
+    if (ip2long($hostname)) {
+      $hostname = gethostbyaddr($hostname);
+    }
+    else {
+      $addr = gethostbyname($hostname);
     }
-    $addr = $addrport[0];
-    $port = $addrport[1];
   }
-  
+  drush_set_context('DRUSH_URI', 'http://' . $hostname . ':' . $uri['port']);
+
   // We delete any registered files here, since they are not caught by Ctrl-C.
   _drush_delete_registered_files();
-  
+
   // Create a new server instance and start it running.
   $server = new DrupalServer(array(
     'addr' => $addr,
-    'port' => $port,
-    'serverid' => 'Drush runserver',
+    'port' => $uri['port'],
+    'path' => $uri['path'],
+    'hostname' => $hostname,
+    'site' => drush_get_context('DRUSH_DRUPAL_SITE', 'default'),
+    'server_id' => 'Drush runserver',
     'php_cgi' => drush_get_option('php-cgi', 'php-cgi') . ' --define auto_prepend_file="' . DRUSH_BASE_PATH . '/commands/runserver/runserver-prepend.php"',
+    'conf_inject' => drush_get_option('conf-inject', array('drupal_http_request_fails' => FALSE)),
+    'user' => $user,
+    'watchdog' => drush_get_option('watchdog', FALSE),
+    'debug' => drush_get_context('DRUSH_DEBUG'),
   ));
   $server->run_forever();
 }
+
+/**
+ * Parse a URI or partial URI (including just a port, host IP or path).
+ *
+ * @param $uri
+ *   String that can contain partial URI.
+ * @return array
+ *   URI array as returned by parse_url.
+ */
+function runserver_parse_uri($uri) {
+  if ($uri[0] == ':') {
+    // ':port/path' shorthand, insert a placeholder hostname to allow parsing.
+    $uri = 'placeholder-hostname' . $uri;
+  }
+  $first_part = substr($uri, 0, strpos($uri, '/'));
+  if (ip2long($first_part)) {
+    // 'IP/path' shorthand, insert a schema to allow parsing.
+    $uri = 'http://' . $uri;
+  }
+  $uri = parse_url($uri);
+  if (empty($uri)) {
+    return drush_set_error('RUNSERVER_INVALID_ADDRPORT', dt('Invalid argument - should be in the "host:port/path" format, numeric (port only) or non-numeric (path only).'));
+  }
+  if (count($uri) == 1 && isset($uri['path'])) {
+    if (is_numeric($uri['path'])) {
+      // Port only shorthand.
+      $uri['port'] = $uri['path'];
+      unset($uri['path']);
+    }
+    else if (ip2long($uri['path'])) {
+      // IP only shorthand.
+      $uri['host'] = $uri['path'];
+      unset($uri['path']);
+    }
+  }
+  if (isset($uri['host']) && $uri['host'] == 'placeholder-hostname') {
+    unset($uri['host']);
+  }
+  return $uri;
+}
\ No newline at end of file
diff --git a/commands/sql/sql.drush.inc b/commands/sql/sql.drush.inc
index 22e162e..7728d1f 100644
--- a/commands/sql/sql.drush.inc
+++ b/commands/sql/sql.drush.inc
@@ -408,7 +408,7 @@ function drush_sql_build_dump_command($table_selection, $db_spec = NULL, $file =
       // Postgres or MySQL equivalents. We may be able to fake some in the
       // future, but for now, let's just support simple dumps.
       $exec .= ' ".dump"';
-      if ($file = drush_get_option('result-file')) {
+      if ($file) {
         $exec .= ' > '. $file;
       }
       break;
@@ -663,8 +663,7 @@ function drush_sql_sanitize() {
 
 /**
  * Get a database specification for the active DB connection. Honors the
- * 'database' and 'target command' line options. If not in a Drupal site,
- * honors a --db-url option.
+ * 'database' and 'target command' line options. Honors a --db-url option.
  *
  * @return
  *   An info array describing a database target.
@@ -673,30 +672,27 @@ function _drush_sql_get_db_spec() {
   $database = drush_get_option('database', 'default');
   $target = drush_get_option('target', 'default');
 
-  // Use --db-url if present.
   if ($url = drush_get_option('db-url')) {
     $url =  is_array($url) ? $url[$database] : $url;
     $db_spec = drush_convert_db_from_db_url($url);
     $db_spec['db_prefix'] = drush_get_option('db-prefix');
     return $db_spec;
   }
-
-  // Otherwise, read settings.php.
-  drush_bootstrap_max(DRUSH_BOOTSTRAP_DRUPAL_CONFIGURATION);
-  switch (drush_drupal_major_version()) {
-    case 6:
-      $url = isset($GLOBALS['db_url']) ? $GLOBALS['db_url'] : drush_get_option('db-url', NULL);
-      $url =  is_array($url) ? $url[$database] : $url;
-      $db_spec = drush_convert_db_from_db_url($url);
-      $db_spec['db_prefix'] = isset($GLOBALS['db_prefix']) ? $GLOBALS['db_prefix'] : drush_get_option('db-prefix', NULL);
-      return $db_spec;
-
-    default:
-      // We don't use DB API here `sql-sync` would have to messily addConnection.
-      if (!isset($GLOBALS['databases']) || !array_key_exists($database, $GLOBALS['databases']) || !array_key_exists($target, $GLOBALS['databases'][$database])) {
-        return NULL;
-      }
-      return $GLOBALS['databases'][$database][$target];
+  elseif (drush_bootstrap(DRUSH_BOOTSTRAP_DRUPAL_CONFIGURATION)) {
+    switch (drush_drupal_major_version()) {
+      case 6:
+        $url = isset($GLOBALS['db_url']) ? $GLOBALS['db_url'] : drush_get_option('db-url', NULL);
+        $url =  is_array($url) ? $url[$database] : $url;
+        $db_spec = drush_convert_db_from_db_url($url);
+        $db_spec['db_prefix'] = isset($GLOBALS['db_prefix']) ? $GLOBALS['db_prefix'] : drush_get_option('db-prefix', NULL);
+        return $db_spec;
+      default:
+        // We don't use DB API here `sql-sync` would have to messily addConnection.
+        if (!isset($GLOBALS['databases']) || !array_key_exists($database, $GLOBALS['databases']) || !array_key_exists($target, $GLOBALS['databases'][$database])) {
+          return NULL;
+        }
+        return $GLOBALS['databases'][$database][$target];
+    }
   }
 }
 
@@ -884,7 +880,7 @@ function _drush_sql_get_credentials($db_spec = NULL) {
       // SQLite doesn't do user management, instead relying on the filesystem
       // for that. So the only info we really need is the path to the database
       // file, and not as a "--key=value" parameter.
-      return ' ' . $db_spec['database'];
+      return ' '  .  $db_spec['database'];
       break;
 
     case 'sqlsrv':
@@ -1042,6 +1038,7 @@ function drush_sql_su($db_spec, $site_alias_record = NULL) {
  *   in a Windows shell. Set TRUE of the CREATE is not running on the bash command line.
  */
 function drush_sql_build_createdb_sql($db_spec, $quoted = FALSE) {
+  $sql = array();
   switch (_drush_sql_get_scheme($db_spec)) {
     case 'mysql':
       $dbname = $quoted ? '`' . $db_spec['database'] . '`' : $db_spec['database'];
@@ -1066,8 +1063,11 @@ function drush_sql_build_createdb_sql($db_spec, $quoted = FALSE) {
  * @return boolean
  */
 function drush_sql_db_exists($db_spec) {
-  $connect_yes_db = _drush_sql_connect($db_spec);
+  if  ($db_spec['driver'] == 'sqlite') {
+    return file_exists($db_spec['database']);
+  }
 
+  $connect_yes_db = _drush_sql_connect($db_spec);
   $database = $db_spec['database'];
   unset($db_spec['database']);
   $connect_no_db = _drush_sql_connect($db_spec);
@@ -1082,8 +1082,6 @@ function drush_sql_db_exists($db_spec) {
       drush_shell_exec("$connect_no_db -t -c \"$sql\"");
       $output = drush_shell_exec_output();
       return (bool)$output[0];
-    case 'sqlite':
-      return file_exists($database);
     case 'sqlsrv':
       // TODO: untested, but the gist is here.
       $sql = "if db_id('$database') IS NOT NULL print 1";
diff --git a/drush.bat b/drush.bat
index dcfcf49..34c1947 100644
--- a/drush.bat
+++ b/drush.bat
@@ -1,3 +1,16 @@
 @echo off
+rem Drush automatically determines the user's home directory by checking for
+rem HOME or HOMEDRIVE/HOMEPATH environment variables, and the temporary
+rem directory by checking for TEMP, TMP, or WINDIR environment variables.
+rem The home path is used for caching Drush commands and the git --reference
+rem cache. The temporary directory is used by various commands, including
+rem package manager for downloading projects.
+rem You may want to specify a path that is not user-specific here; e.g., to
+rem keep cache files on the same filesystem, or to share caches with other
+rem users.
+
+rem set HOME=H:/drush
+rem set TEMP=H:/drush
+
 REM See http://drupal.org/node/506448 for more information.
 @php.exe "%~dp0drush.php" %* --php="php.exe"
diff --git a/drush.complete.sh b/drush.complete.sh
index de38bc5..f1924b4 100644
--- a/drush.complete.sh
+++ b/drush.complete.sh
@@ -3,7 +3,7 @@
 # BASH completion script for Drush.
 #
 # Place this in your /etc/bash_completion.d/ directory or source it from your
-# ~/.bash_completion file.
+# ~/.bash_completion or ~/.bash_profile  files.
 
 # Ensure drush is available.
 have drush || return
diff --git a/examples/example.aliases.drushrc.php b/examples/example.aliases.drushrc.php
index 6d68359..5932d48 100644
--- a/examples/example.aliases.drushrc.php
+++ b/examples/example.aliases.drushrc.php
@@ -159,6 +159,8 @@
  * - 'php': path to custom php interpreter, defaults to /usr/bin/php
  * - 'php-options': commandline options for php interpreter, you may
  *   want to set this to '-d error_reporting="E_ALL^E_DEPRECATED"'
+ * - 'variables' : An array of name/value pairs which override Drupal variables.
+ *    These values take precedence even over settings.php variable overrides.
  * - 'command-specific': These options will only be set if the alias
  *   is used with the specified command.  In the example below, the option
  *   `--no-cache` will be selected whenever the @stage alias
@@ -191,6 +193,9 @@
 #      '%files' => 'sites/mydrupalsite.com/files',
 #      '%custom' => '/my/custom/path',
 #     ),
+#     'variables => array(
+#        site_name => 'My Drupal site',
+#      ),
 #     'command-specific' => array (
 #       'sql-sync' => array (
 #         'no-cache' => TRUE,
@@ -200,6 +205,7 @@
 #$aliases['dev'] = array(
 #    'uri' => 'dev.mydrupalsite.com',
 #    'root' => '/path/to/drupal/root',
+#    'variables' => array('mail_system' => array('default-system' => 'DevelMailLog')),
 #  );
 #$aliases['server'] = array(
 #    'remote-host' => 'mystagingserver.myisp.com',
diff --git a/examples/example.drushrc.php b/examples/example.drushrc.php
index 40fd2a0..a1d5e48 100644
--- a/examples/example.drushrc.php
+++ b/examples/example.drushrc.php
@@ -1,6 +1,6 @@
 <?php
 
-/*
+/**
  * Examples of valid statements for a drushrc.php file. Use this file to cut down on
  * typing of options and avoid mistakes.
  *
@@ -57,18 +57,18 @@
 // Drush shell aliases act similar to git aliases.
 // See https://git.wiki.kernel.org/index.php/Aliases#Advanced.
 // For best success, define these in drushrc files located in #6-3 above.
-# $options['shell-aliases'] = array(
-#   'pull' => '!git pull', // we've all done it.
-#   'pulldb' => '!git pull && drush updatedb',
-#   'noncore' => 'pm-list --no-core',
-#   'wipe' => 'cache-clear all',
-# );
+# $options['shell-aliases']['pull'] = '!git pull'; // We've all done it.
+# $options['shell-aliases']['pulldb'] = '!git pull && drush updatedb';
+# $options['shell-aliases']['noncore'] = 'pm-list --no-core';
+# $options['shell-aliases']['wipe'] = 'cache-clear all';
+// Add a 'pm-clone' to simplify (cached) git cloning from drupal.org.
+# $options['shell-aliases']['pm-clone'] = 'pm-download --gitusername=YOURUSERNAME --package-handler=git_drupalorg --cache';
 
 // Load a drushrc.php configuration file from the current working directory.
 # $options['c'] = '.';
 
 // Disable the nag warning for Windows.
-// Consider improving Windows support: http://drupal.org/node/766080.
+// @see http://drupal.org/node/766080
 # $options['check_os'] = FALSE;
 
 // Control automatically check for updates in pm-updatecode and drush version.
@@ -102,13 +102,13 @@
 // Specify directory where sql-dump should store backups of database
 // dumps.  @DATABASE is replaced with the name of the database being
 // dumped, and @DATE is replaced with the current time and date of the
-// dump.  TRUE will cause sql-dump to use the same backup directory that
-// pm-updatecode does.
-//
+// dump.
 // If set, this can be explicitly overridden by specifying --result-file
 // on the commandline.  The default behavior of dumping to
 // STDOUT can be achieved via --result-file=0
 # $options['result-file'] = '/path/to/backup/dir/@DATABASE_@DATE.sql';
+// TRUE will cause sql-dump to use the same backup directory that pm-updatecode
+// does.
 # $options['result-file'] = TRUE;
 
 // Enable verbose mode.
@@ -117,12 +117,14 @@
 // Show database passwords in 'status' and 'sql-conf' commands
 # $options['show-passwords'] = 1;
 
-// Default logging level for php notices.  Defaults to "notice"; set to "warning"
-// if doing drush development.  Also make sure that error_reporting is set to E_ALL
-// in your php configuration file.  See 'drush status' for the path to your php.ini file.
+// Default logging level for PHP notices. Defaults to "notice".
+// Set to "warning" when doing drush development. Also make sure that
+// error_reporting is set to E_ALL in your php configuration file.
+// See 'drush status' for the path to your php.ini file.
 # $options['php-notices'] = 'warning';
 
-// Specify options to pass to ssh in backend invoke. (Default is to prohibit password authentication; uncomment to change)
+// Specify options to pass to ssh in backend invoke.
+// Default is to prohibit password authentication.
 # $options['ssh-options'] = '-o PasswordAuthentication=no';
 
 // Set 'remote-os' to 'Windows' to make drush use Windows shell escape
@@ -135,54 +137,57 @@
 // version of rsync installed on any system you are using with
 // drush).  Note that drush requires at least rsync version 2.6.4
 // for some functions to work correctly.
-//
 // Note that this option can also be set in a site alias.  This
 // is preferable if newer versions of rsync are available on some
 // of the systems you use.
 // See: http://drupal.org/node/955092
 # $options['rsync-version'] = '2.6.9';
 
-/*
-* The output charset suitable to pass to iconv PHP function as out_charset
-* parameter. Drush will convert its output from UTF-8 to the charset specified
-* here. It is possible to use //TRANSLIT and //IGNORE charset name suffixes
-* (see iconv documentation). If not defined conversion will not be performed.
-*/
+/**
+ * The output charset suitable to pass to iconv PHP function as out_charset parameter.
+ *
+ * Drush will convert its output from UTF-8 to the charset specified here. It is
+ * possible to use //TRANSLIT and //IGNORE charset name suffixes (see iconv
+ * documentation). If not defined conversion will not be performed.
+ */
 # $options['output_charset'] = 'ISO-8859-1';
 # $options['output_charset'] = 'KOI8-R//IGNORE';
 # $options['output_charset'] = 'ISO-8859-1//TRANSLIT';
 
-/*
- * Multiple command execution options
+/**
+ * Multiple command execution options.
+ *
+ * By default, drush will prepend the name of the site to the output of any
+ * multiple-site command execution. To disable this behavior, set the --no-label
+ * option.
  */
-// By default, drush will prepend the name of the
-// site to the output of any multiple-site command
-// execution.  To disable this behavior, set the
-// --no-label option
 # $options['no-label'] = TRUE;
 
-/*
+/**
  * Customize this associative array with your own tables. This is the list of
  * tables whose *data* is skipped by the 'sql-dump' and 'sql-sync' commands when
  * a structure-tables-key is provided. You may add new tables to the existing
  * array or add a new element.
  */
-$options['structure-tables'] = array(
- 'common' => array('cache', 'cache_filter', 'cache_menu', 'cache_page', 'history', 'sessions', 'watchdog'),
-);
+# $options['structure-tables']['common'] = array('cache', 'cache_filter', 'cache_menu', 'cache_page', 'history', 'sessions', 'watchdog');
 
-/*
+/**
  * Customize this associative array with your own tables. This is the list of
  * tables that are entirely omitted by the 'sql-dump' and 'sql-sync' commands
  * when a skip-tables-key is provided. This is useful if your database contains
  * non Drupal tables used by some other application or during a migration for
  * example. You may add new tables to the existing array or add a new element.
  */
-$options['skip-tables'] = array(
- 'common' => array('migration_data1', 'migration_data2'),
-);
+# $options['skip-tables']['common'] = array('migration_data1', 'migration_data2');
 
-/*
+/**
+ * Override specific entries in Drupal's 'variable' table or settings.php
+ */
+# $options['variables']['site_name'] = 'My Drupal site';
+# $options['variables']['theme_default'] = 'minnelli';
+# $options['variables']['anonymous'] = 'Visitor';
+
+/**
  * Command-specific options
  *
  * To define options that are only applicable to certain commands,
@@ -223,20 +228,3 @@ $options['skip-tables'] = array(
 // you can use the regular shell command by typing in the full path
 // to the command (e.g. /bin/grep).
 # $command_specific['core-cli'] = array('override' => 'help,dd,sa');
-
-/**
- * Variable overrides:
- *
- * To override specific entries in the 'variable' table for this site,
- * set them here. Any configuration setting from the 'variable'
- * table can be given a new value. We use the $override global here
- * to make sure that changes from settings.php can not wipe out these
- * settings.
- *
- * Remove the leading hash signs to enable.
- */
-# $override = array(
-#   'site_name' => 'My Drupal site',
-#   'theme_default' => 'minnelli',
-#   'anonymous' => 'Visitor',
-# );
diff --git a/examples/sandwich.drush.inc b/examples/sandwich.drush.inc
index 677e303..2993b16 100644
--- a/examples/sandwich.drush.inc
+++ b/examples/sandwich.drush.inc
@@ -38,7 +38,7 @@ function sandwich_drush_command() {
   $items['make-me-a-sandwich'] = array(
     'description' => "Makes a delicious sandwich.",
     'arguments' => array(
-      'filling' => 'The type of the sandwich (turkey, cheese, etc.)',
+      'filling' => 'The type of the sandwich (turkey, cheese, etc.). Defaults to ascii.',
     ),
     'options' => array(
       'spreads' => 'Comma delimited list of spreads (e.g. mayonnaise, mustard)',
@@ -65,6 +65,8 @@ function sandwich_drush_command() {
   return $items;
 }
 
+
+
 /**
  * Implementation of hook_drush_help().
  *
@@ -169,9 +171,20 @@ function drush_sandwich_make_me_a_sandwich($filling = 'ascii') {
 
   if (drush_get_context('DRUSH_NOCOLOR')) {
     $filename = dirname(__FILE__) . '/sandwich-nocolor.txt';
-  } 
+  }
   else {
     $filename = dirname(__FILE__) . '/sandwich.txt';
   }
   drush_print(file_get_contents($filename));
 }
+
+/**
+ * Command argument complete callback. Provides argument
+ * values for shell completion.
+ *
+ * @return
+ *  Array of popular fillings.
+ */
+function sandwich_make_me_a_sandwich_complete() {
+  return array('values' => array('turkey', 'cheese', 'jelly', 'butter'));
+}
diff --git a/includes/backend.inc b/includes/backend.inc
index a8c1ec9..2bc317e 100644
--- a/includes/backend.inc
+++ b/includes/backend.inc
@@ -803,7 +803,7 @@ function _drush_backend_argument_string($data, $os = NULL) {
   $options = array();
 
   foreach ($data as $key => $value) {
-    if (!is_array($value) && !is_object($value) && !is_null($value) && ($value != '')) {
+    if (!is_array($value) && !is_object($value) && !is_null($value)) {
       if (substr($key,0,1) != '#') {
         $options[$key] = $value;
       }
diff --git a/includes/bootstrap.inc b/includes/bootstrap.inc
index c4e9992..20d189b 100644
--- a/includes/bootstrap.inc
+++ b/includes/bootstrap.inc
@@ -318,6 +318,9 @@ function drush_bootstrap_to_phase($max_phase_index) {
  *
  * @param $max_phase_index
  *   Only attempt bootstrap to the specified level.
+ *
+ *  @return int
+ *    The maximum phase to which we bootstrapped.
  */
 function drush_bootstrap_max($max_phase_index = FALSE) {
   $phases = _drush_bootstrap_phases();
@@ -749,15 +752,31 @@ function _drush_bootstrap_redo_drupal_site() {
  * We process and store a normalized set of database credentials
  * from the loaded configuration file, so we can validate them
  * and access them easily in the future.
+ *
+ * Also override Drupal variables as per --variables option.
  */
 function _drush_bootstrap_drupal_configuration() {
-  global $conf, $drush_conf_override;
+  global $conf;
 
   drupal_bootstrap(DRUPAL_BOOTSTRAP_CONFIGURATION);
 
-  // Overriding the $conf array from drupal CONFIGURATION bootstrap with the
-  // Overrides we collected on the loaded config files on DRUSH_BOOTSTRAP_DRUSH
-  $conf = is_array($conf) && is_array($drush_conf_override) ? array_merge($conf, $drush_conf_override) : $conf;
+  // Unset drupal error handler and restore drush's one.
+  if (drush_drupal_major_version() >= 7) {
+    restore_error_handler();
+  }
+
+  // Force Drupal6 not to store queries since we are not outputting them.
+  // Don't run poormanscron during Drush request (D7+).
+  $override = array(
+    'dev_query' => FALSE,
+    'cron_safe_threshold' => 0,
+  );
+  $current_override = drush_get_option_list('variables');
+  foreach ( $current_override as $pair) {
+    list($name, $value) = explode('=', $pair, 2);
+    $override[$name] = $value;
+  }
+  $conf = is_array($conf) ? array_merge($conf, $override) : $conf;
 
   // Populate the DRUSH_DB_CREDENTIALS with the fields loaded from the configuration.
   $creds = array();
@@ -836,6 +855,12 @@ function _drush_bootstrap_drupal_full() {
   if (!drush_get_context('DRUSH_QUIET', FALSE)) {
     ob_end_clean();
   }
+
+  // Unset drupal error handler and restore drush's one.
+  if (drush_drupal_major_version() == 6) {
+    restore_error_handler();
+  }
+
   // If needed, prod module_implements() to recognize our system_watchdog() implementation.
   $dogs = module_implements('watchdog');
   if (!in_array('system', $dogs)) {
diff --git a/includes/cache.inc b/includes/cache.inc
index 0119b9d..415e59b 100644
--- a/includes/cache.inc
+++ b/includes/cache.inc
@@ -378,12 +378,12 @@ class DrushFileCache implements DrushCacheInterface {
     $bin_dir = $this->cacheDirectory();
     $files = array();
     if (empty($cid)) {
-      drush_delete_dir($bin_dir);
+      drush_delete_dir($bin_dir, TRUE);
     }
     else {
       if ($wildcard) {
         if ($cid == '*') {
-          drush_delete_dir($bin_dir);
+          drush_delete_dir($bin_dir, TRUE);
         }
         else {
           $matches = drush_scan_directory($bin_dir, "/^$cid/", array('.', '..'));
diff --git a/includes/command.inc b/includes/command.inc
index 6b5e256..3660e07 100644
--- a/includes/command.inc
+++ b/includes/command.inc
@@ -126,6 +126,7 @@ function _drush_invoke($command, $args, $defined_in_commandfile) {
         // Only the 'main' callback can send data to backend.
         if ($var_hook == $hook) {
           drush_backend_set_result($result);
+          $return = $result;
         }
         _drush_log_drupal_messages();
         if (drush_get_error() || ($result === FALSE)) {
@@ -163,9 +164,10 @@ function _drush_invoke($command, $args, $defined_in_commandfile) {
         drush_log(dt("Changes made in !func have been rolled back.", array('!func' => $func)), 'rollback');
       }
     }
+    return $rollback;
   }
 
-  return !$rollback;
+  return $return;
 }
 
 /**
diff --git a/includes/context.inc b/includes/context.inc
index f1c30d2..9f51b67 100644
--- a/includes/context.inc
+++ b/includes/context.inc
@@ -83,13 +83,19 @@ function drush_context_names() {
 /**
  * Return a list of possible drushrc file locations.
  *
+ * @context
+ *   A valid drush context from drush_context_names().
+ * @prefix
+ *   Optional. Specify a prefix to prepend to ".drushrc.php" when looking
+ *   for config files. Most likely used by contrib commands.
  * @return
  *   An associative array containing possible config files to load
  *   The keys are the 'context' of the files, the values are the file
  *   system locations.
  */
-function _drush_config_file($context) {
+function _drush_config_file($context, $prefix = NULL) {
   $configs = array();
+  $config_file = $prefix ? $prefix . '.' . 'drushrc.php' : 'drushrc.php';
 
   // Did the user explicitly specify a config file?
   if ($config = drush_get_option(array('c', 'config'))) {
@@ -100,28 +106,28 @@ function _drush_config_file($context) {
   }
 
   if ($site_path = drush_get_context('DRUSH_DRUPAL_SITE_ROOT')) {
-    $configs['site'] = $site_path . "/drushrc.php";
+    $configs['site'] = $site_path . "/" . $config_file;
   }
 
   if ($drupal_root = drush_get_context('DRUSH_DRUPAL_ROOT')) {
-    $configs['drupal'] = $drupal_root . '/drushrc.php';
+    $configs['drupal'] = $drupal_root . '/' . $config_file;
   }
 
   // in the user home directory
   if (!is_null(drush_server_home())) {
-    $configs['user'] = drush_server_home() . '/.drushrc.php';
+    $configs['user'] = drush_server_home() . '/.' . $config_file;
   }
 
   // in $HOME/.drush directory
   if (!is_null(drush_server_home())) {
-    $configs['home.drush'] = drush_server_home() . '/.drush/drushrc.php';
+    $configs['home.drush'] = drush_server_home() . '/.drush/' . $config_file;
   }
 
   // In the system wide configuration folder.
-  $configs['system'] = drush_get_context('ETC_PREFIX', '') . '/etc/drush/drushrc.php';
+  $configs['system'] = drush_get_context('ETC_PREFIX', '') . '/etc/drush/' . $config_file;
 
   // in the drush installation folder
-  $configs['drush'] = dirname(__FILE__) . '/../drushrc.php';
+  $configs['drush'] = dirname(__FILE__) . '/../' . $config_file;
 
   return empty($configs[$context]) ? '' : $configs[$context];
 }
@@ -157,13 +163,6 @@ function drush_load_config_file($context, $config) {
 }
 
 function drush_set_config_options($context, $options, $override = array()) {
-  global $drush_conf_override;
-
-  // Only reset $drush_conf_override if the array is not set, otherwise keep old values and append new values to it.
-  if (!isset($drush_conf_override)) {
-    $drush_conf_override = array();
-  }
-
   // Copy 'config-file' into 'context-path', converting to an array to hold multiple values if necessary
   if (isset($options['config-file'])) {
     if (isset($options['context-path'])) {
@@ -178,29 +177,6 @@ function drush_set_config_options($context, $options, $override = array()) {
   drush_set_config_special_contexts($options);
 
   drush_set_context($context, $options);
-
-  // Instruct core not to store queries since we are not outputting them.
-  // Don't run poormanscron during drush request (D7+).
-  $defaults = array(
-    'dev_query' => FALSE,
-    'cron_safe_threshold' => 0,
-  );
-  foreach ($defaults as $key => $value) {
-    // This can be overridden by a command or a drushrc file if needed.
-    if (!isset($drush_conf_override[$key])) {
-      $drush_conf_override[$key] = $value;
-    }
-  }
-
-  /**
-   * Allow the drushrc.php file to override $conf settings.
-   * This is a separate variable because the $conf array gets
-   * initialized to an empty array, in the drupal bootstrap process,
-   * and changes in settings.php would wipe out the drushrc.php settings.
-   */
-  if (!empty($override)) {
-    $drush_conf_override = array_merge($drush_conf_override, $override);
-  }
 }
 
 /**
diff --git a/includes/drupal.inc b/includes/drupal.inc
index 31c6b56..8746085 100644
--- a/includes/drupal.inc
+++ b/includes/drupal.inc
@@ -117,4 +117,8 @@ function _drush_log_update_sql($ret) {
       }
     }
   }
+}
+
+function drush_find_profiles($drupal_root , $key = 'name') {
+  return drush_scan_directory($drupal_root . '/profiles', "/.*\.profile$/", array('.', '..', 'CVS', 'tests'), 0, 2, $key);
 }
\ No newline at end of file
diff --git a/includes/drush.inc b/includes/drush.inc
index 0785087..4b16200 100644
--- a/includes/drush.inc
+++ b/includes/drush.inc
@@ -307,12 +307,12 @@ function _convert_csv_to_array($args) {
  *   Return a reduced set of important options. Used by help command.
  *
  * @return
- *   An associative array containing the option definition as the key, 
+ *   An associative array containing the option definition as the key,
  *   and a descriptive array for each of the available options.  The array
  *   elements for each item are:
  *
  *     - short-form: The shortcut form for specifying the key on the commandline.
- *     - never-post: If TRUE, backend invoke will never POST this item's value 
+ *     - never-post: If TRUE, backend invoke will never POST this item's value
  *       on STDIN; it will always be sent as a commandline option.
  *     - never-propagate: If TRUE, backend invoke will never pass this item on
  *       to the subcommand being executed.
@@ -341,6 +341,7 @@ function drush_get_global_options($brief = FALSE) {
     $options['user']                = array('short-form' => 'u', 'description' => dt("Specify a Drupal user to login with. May be a name or a number."));
     $options['backend']             = array('short-form' => 'b', 'never-propagate' => TRUE, 'description' => dt("Hide all output and return structured data (internal use only)."));
     $options['choice']              = array('description' => dt("Provide an answer to a multiple-choice prompt."));
+    $options['variables']           = array('description' => dt("Comma delimited list of name=value pairs. These values take precedence even over settings.php variable overrides."));
     $options['no-label']            = array('description' => dt("Remove the site label that drush includes in multi-site command output(e.g. `drush @site1,@site2 status`)."));
     $options['nocolor']             = array('context' => 'DRUSH_NOCOLOR', 'description' => dt("Suppress color highlighting on log messages."));
     $options['show-passwords']      = array('description' => dt("Show database passwords in commands that display connection information."));
diff --git a/includes/environment.inc b/includes/environment.inc
index d5d18ff..3e708ff 100644
--- a/includes/environment.inc
+++ b/includes/environment.inc
@@ -693,6 +693,14 @@ function drush_get_extensions() {
 }
 
 /**
+ *
+ */
+function drush_drupal_required_modules($modules) {
+  drush_include_engine('drupal', 'environment');
+  return _drush_drupal_required_modules($modules);
+}
+
+/**
  * Return the default theme.
  *
  * @return
diff --git a/includes/exec.inc b/includes/exec.inc
index c00154a..464b48c 100644
--- a/includes/exec.inc
+++ b/includes/exec.inc
@@ -290,5 +290,56 @@ function drush_shell_exec_output() {
 }
 
 /**
+ * Starts a background browser/tab for the current site or a specified URL.
+ *
+ * Uses a non-blocking proc_open call, so Drush execution will continue.
+ *
+ * @param $uri
+ *   Optional URI or site path to open in browser. If omitted, or if a site path
+ *   is specified, the current site home page uri will be prepended if the sites
+ *   hostname resolves.
+ * @return
+ *   TRUE if browser was opened, FALSE if browser was disabled by the user or a,
+ *   default browser could not be found.
+ */
+function drush_start_browser($uri = NULL) {
+  if (!parse_url($uri, PHP_URL_HOST)) {
+    $site = drush_get_context('DRUSH_URI');
+    $host = parse_url($site, PHP_URL_HOST);
+    // Validate that the host part of the URL resolves, so we don't attempt to
+    // open the browser for http://default or similar invalid hosts.
+    $hosterror = gethostbyname($host) == $host;
+    $iperror = ip2long($host) && gethostbyaddr($host) == $host;
+    if ($hosterror && $iperror) {
+      drush_log(dt('!host does not appear to be a resolvable hostname or IP, not starting browser.', array('!host' => $host)), 'warning');
+      return FALSE;
+    }
+    $uri = $site . '/' . ltrim($uri, '/');
+  }
+  if ($browser = drush_get_option('browser', TRUE)) {
+    if ($browser === TRUE) {
+      // See if we can find an OS helper to open URLs in default browser.
+      if (drush_shell_exec('which xdg-open')) {
+        $browser = 'xdg-open';
+      }
+      else if (drush_shell_exec('which open')) {
+        $browser = 'open';
+      }
+      else {
+        // Can't find a valid browser.
+        $browser = FALSE;
+      }
+    }
+    if ($browser && !drush_get_context('DRUSH_SIMULATE')) {
+      $pipes = array();
+      drush_log(dt('Opening browser at !uri', array('!uri' => $uri)));
+      proc_close(proc_open($browser . ' ' . drush_escapeshellarg($uri) . ' 2> /dev/null &', array(), $pipes));
+      return TRUE;
+    }
+  }
+  return FALSE;
+}
+
+/**
  * @} End of "defgroup commandwrappers".
  */
diff --git a/includes/filesystem.inc b/includes/filesystem.inc
index d544ac1..71abe92 100644
--- a/includes/filesystem.inc
+++ b/includes/filesystem.inc
@@ -135,7 +135,7 @@ function drush_copy_dir($src, $dest, $overwrite = FALSE) {
   // Preflight based on $overwrite if $dest exists.
   if (file_exists($dest)) {
     if ($overwrite) {
-      drush_op('drush_delete_dir', $dest);
+      drush_op('drush_delete_dir', $dest, TRUE);
     }
     else {
       return drush_set_error('DRUSH_DESTINATION_EXISTS', dt('Destination directory !dest already exists.', array('!dest' => $dest)));
@@ -207,7 +207,7 @@ function drush_move_dir($src, $dest, $overwrite = FALSE) {
   // Preflight based on $overwrite if $dest exists.
   if (file_exists($dest)) {
     if ($overwrite) {
-      drush_op('drush_delete_dir', $dest);
+      drush_op('drush_delete_dir', $dest, TRUE);
     }
     else {
       return drush_set_error('DRUSH_DESTINATION_EXISTS', dt('Destination directory !dest already exists.', array('!dest' => $dest)));
@@ -234,7 +234,7 @@ function drush_move_dir($src, $dest, $overwrite = FALSE) {
   // If 'rename' fails, then we will use copy followed
   // by a delete of the source.
   if (drush_copy_dir($src, $dest)) {
-    drush_op('drush_delete_dir', $src);
+    drush_op('drush_delete_dir', $src, TRUE);
     return TRUE;
   }
 
@@ -278,9 +278,9 @@ function drush_save_data_to_temp_file($data) {
  * path is not valid in some setups for Mac.
  */
 function drush_find_tmp() {
-  static $temporary_directory = NULL;
+  static $temporary_directory;
 
-  if (is_null($temporary_directory)) {
+  if (!isset($temporary_directory)) {
     $directories = array();
 
     // Operating system specific dirs.
@@ -297,7 +297,10 @@ function drush_find_tmp() {
       }
       $windir = getenv('WINDIR');
       if (isset($windir)) {
-        $directories[] = $windir;
+        // WINDIR itself is not writable, but it always contains a /Temp dir,
+        // which is the system-wide temporary directory on older versions. Newer
+        // versions only allow system processes to use it.
+        $directories[] = $windir . '/Temp';
       }
     }
     else {
@@ -388,7 +391,7 @@ function _drush_delete_registered_files() {
     // though they did not need to.
     if (file_exists($file)) {
       if (is_dir($file)) {
-        drush_delete_dir($file);
+        drush_delete_dir($file, TRUE);
       }
       else {
         @chmod($dir, 0777); // Make file writeable
diff --git a/includes/sitealias.inc b/includes/sitealias.inc
index efd53d7..01c6101 100644
--- a/includes/sitealias.inc
+++ b/includes/sitealias.inc
@@ -632,18 +632,18 @@ function sitealias_get_databases_from_record(&$alias_record) {
  * which will be used to first add the database information to the
  * alias records, invoking sql-conf to look them up if necessary.
  *
- * The options 'database' and 'target' are used to specify which 
- * specific database should be fetched from the database record; 
+ * The options 'database' and 'target' are used to specify which
+ * specific database should be fetched from the database record;
  * they may appear in the alias definition, or may be taken from the
  * command line options.  The values 'default' and 'default' are
  * used if these options are not specified in either location.
  *
  * Note that in the context of sql-sync, the site alias record will
- * be taken from one of the source or target aliases 
- * (e.g. `drush sql-sync @source @target`), which will be overlayed with 
+ * be taken from one of the source or target aliases
+ * (e.g. `drush sql-sync @source @target`), which will be overlayed with
  * any options that begin with 'source-' or 'target-', respectively.
  * Therefore, the commandline options 'source-database' and 'source-target'
- * (or 'target-database' and 'source-target') may also affect the operation 
+ * (or 'target-database' and 'source-target') may also affect the operation
  * of this function.
  */
 function drush_sitealias_get_db_spec(&$alias_record, $default_to_self = FALSE) {
@@ -1316,6 +1316,7 @@ function drush_convert_db_from_db_url($db_url) {
     'pass' => NULL,
     'host' => NULL,
     'port' => NULL,
+    'path' => NULL,
     'database' => NULL,
   );
   $url = (object)array_map('urldecode', $url);
@@ -1324,10 +1325,10 @@ function drush_convert_db_from_db_url($db_url) {
     'username' => $url->user,
     'password' => $url->pass,
     'port' => $url->port,
-    'host' => $url->host,
+    'host' => $url->scheme == 'sqlite' ? '' : $url->host,
     // Remove leading / character from database names, unless we're installing
     // to SQLite (which won't have a slash there unless it's part of a path).
-    'database' => $url->scheme === 'sqlite' ? $url->path : substr($url->path, 1)
+    'database' => $url->scheme == 'sqlite'  ? $url->host  . $url->path : substr($url->path, 1),
   );
 }
 
@@ -1702,7 +1703,7 @@ function drush_sitealias_evaluate_path($path, &$additional_options, $local_only
   // When calculating a path for use with rsync, we must correct
   // absolute paths in the form c:\path when cwrsync is in use.
   $path = drush_correct_absolute_path_for_exec($path, $os);
-  
+
   // If there is a $machine component, to the path, then
   // add it to the beginning
   $evaluated_path = drush_escapeshellarg($path, $os);
diff --git a/tests/archiveDumpTest.php b/tests/archiveDumpTest.php
index ca2523e..cd4884c 100644
--- a/tests/archiveDumpTest.php
+++ b/tests/archiveDumpTest.php
@@ -35,7 +35,9 @@ class archiveDumpCase extends Drush_CommandTestCase {
     $untar_dest = UNISH_SANDBOX . '/untar';
     $exec = sprintf('mkdir %s && cd %s && tar xzf %s/%s', $untar_dest, $untar_dest, UNISH_SANDBOX, $dump_dest);
     $this->execute($exec);
-    $this->execute(sprintf('head %s/unish_%s.sql | grep "MySQL dump"', $untar_dest, $uri));
+    if (strpos(UNISH_DB_URL, 'mysql') !== FALSE) {
+      $this->execute(sprintf('head %s/unish_%s.sql | grep "MySQL dump"', $untar_dest, $uri));
+    }
     $this->execute('test -f ' . $untar_dest . '/MANIFEST.ini');
     $this->execute('test -d ' . $untar_dest . '/' . $docroot);
   }
diff --git a/tests/drush_testcase.inc b/tests/drush_testcase.inc
index dfe2dc5..a731b89 100644
--- a/tests/drush_testcase.inc
+++ b/tests/drush_testcase.inc
@@ -130,6 +130,10 @@ abstract class Drush_TestCase extends PHPUnit_Framework_TestCase {
     return getenv('CACHE_PREFIX') . '/' . $subdir;
   }
 
+  function db_url($env) {
+    return substr(UNISH_DB_URL, 0, 6) == 'sqlite'  ?  "sqlite://sites/$env/files/unish.sqlite" : UNISH_DB_URL . '/unish_' . $env;
+  }
+
   function setUpDrupal($num_sites = 1, $install = FALSE, $version_string = '7', $profile = NULL) {
     $sites_subdirs_all = array('dev', 'stage', 'prod', 'retired', 'elderly', 'dead', 'dust');
     $sites_subdirs = array_slice($sites_subdirs_all, 0, $num_sites);
@@ -138,7 +142,8 @@ abstract class Drush_TestCase extends PHPUnit_Framework_TestCase {
     if (is_null($profile)) {
       $profile = substr($version_string, 0, 1) >= 7 ? 'testing' : 'default';
     }
-    $cache_keys = array($num_sites, $install ? 'install' : 'noinstall', $version_string, $profile);
+    $db_driver = parse_url(UNISH_DB_URL, PHP_URL_SCHEME);
+    $cache_keys = array($num_sites, $install ? 'install' : 'noinstall', $version_string, $profile, $db_driver);
     $source = $this->directory_cache('environments') . '/' . implode('-', $cache_keys) . '.tar.gz';
     if (file_exists($source)) {
       $this->log('Cache HIT. Environment: ' . $source, 'verbose');
@@ -162,7 +167,7 @@ abstract class Drush_TestCase extends PHPUnit_Framework_TestCase {
     // Stash details about each site.
     foreach ($sites_subdirs as $subdir) {
       $this->sites[$subdir] = array(
-        'db_url' => UNISH_DB_URL . '/unish_' . $subdir,
+        'db_url' => $this->db_url($subdir),
       );
       // Make an alias for the site
       $alias_definition = array($subdir => array('root' => $root,  'uri' => $subdir));
@@ -191,7 +196,7 @@ abstract class Drush_TestCase extends PHPUnit_Framework_TestCase {
     if ($install) {
       $options = array(
         'root' => $root,
-        'db-url' => UNISH_DB_URL . '/unish_' . $env,
+        'db-url' => $this->db_url($env),
         'sites-subdir' => $env,
         'yes' => NULL,
         'quiet' => NULL,
diff --git a/tests/phpunit.xml.dist b/tests/phpunit.xml.dist
index 45d27c1..c277994 100644
--- a/tests/phpunit.xml.dist
+++ b/tests/phpunit.xml.dist
@@ -10,6 +10,7 @@
     <!--DB User must have create/drop permissions-->
     <!-- <var name="UNISH_DB_URL" value="mysql://root:@127.0.0.1"/> -->
     <!-- <var name="UNISH_DB_URL" value="pgsql://postgres:@localhost"/>-->
+    <!-- <var name="UNISH_DB_URL" value="sqlite://none/of/this/matters"/> -->
 
     <!--User must have write permissions to this directory.-->
     <!--If not supplied, defaults to sys_get_tmp_dir().-->
diff --git a/tests/siteUpgradeTest.php b/tests/siteUpgradeTest.php
index 62760b1..ff3eb1a 100644
--- a/tests/siteUpgradeTest.php
+++ b/tests/siteUpgradeTest.php
@@ -14,6 +14,11 @@
 
 class siteUpgradeCase extends Drush_CommandTestCase {
   function testUpgrade() {
+    if (strpos(UNISH_DB_URL, 'sqlite') !== FALSE) {
+      $this->markTestSkipped('Drupal 6 does not run on SQLite.');
+      return;
+    }
+
     $sites = $this->setUpDrupal(1, TRUE, '6');
     $root = $this->webroot();
 
diff --git a/tests/sqlSyncTest.php b/tests/sqlSyncTest.php
index 0060409..d5b9772 100644
--- a/tests/sqlSyncTest.php
+++ b/tests/sqlSyncTest.php
@@ -18,6 +18,11 @@ class sqlSyncTest extends Drush_CommandTestCase {
    * General handling of site aliases will be in sitealiasTest.php.
    */
   public function testLocalSqlSync() {
+    if (strpos(UNISH_DB_URL, 'sqlite') !== FALSE) {
+      $this->markTestSkipped('SQL Sync does not apply to SQLite.');
+      return;
+    }
+
     $sites = $this->setUpDrupal(2, TRUE);
     $dump_dir = UNISH_SANDBOX . "/dump-dir";
     mkdir($dump_dir);