diff --cc core/modules/comment/comment.admin.inc
index 2bfce3d,0418b1d..0000000
--- a/core/modules/comment/comment.admin.inc
+++ b/core/modules/comment/comment.admin.inc
@@@ -376,7 -312,5 +376,7 @@@ function comment_confirm_delete_submit(
    // Clear the cache so an anonymous user sees that his comment was deleted.
    cache_invalidate_tags(array('content' => TRUE));
  
-   $entity = entity_load($comment->entity_type->value, $comment->entity_id->value);
 -  $form_state['redirect'] = "node/{$comment->nid->target_id}";
++  $entity = entity_load($comment->entity_type->value, $comment->entity_id->target_id);
 +  $uri = $entity->uri();
 +  $form_state['redirect'] = $uri['path'];
  }
diff --cc core/modules/comment/comment.api.php
index 7218931,793d9ad..0000000
--- a/core/modules/comment/comment.api.php
+++ b/core/modules/comment/comment.api.php
@@@ -34,9 -34,7 +34,9 @@@ function hook_comment_presave(Drupal\co
   */
  function hook_comment_insert(Drupal\comment\Comment $comment) {
    // Reindex the node when comments are added.
 -  search_touch_node($comment->nid->target_id);
 +  if ($comment->entity_type == 'node') {
-     search_touch_node($comment->entity_id->value);
++    search_touch_node($comment->entity_id->target_id);
 +  }
  }
  
  /**
@@@ -47,9 -45,7 +47,9 @@@
   */
  function hook_comment_update(Drupal\comment\Comment $comment) {
    // Reindex the node when comments are updated.
 -  search_touch_node($comment->nid->target_id);
 +  if ($comment->entity_type == 'node') {
-     search_touch_node($comment->entity_id->value);
++    search_touch_node($comment->entity_id->target_id);
 +  }
  }
  
  /**
diff --cc core/modules/comment/comment.module
index b624f5f,14df557..0000000
--- a/core/modules/comment/comment.module
+++ b/core/modules/comment/comment.module
@@@ -976,7 -945,7 +976,7 @@@ function comment_links(Comment $comment
        );
        $links['comment-reply'] = array(
          'title' => t('reply'),
-         'href' => "comment/reply/{$comment->entity_type->value}/{$comment->entity_id->value}/{$comment->field_name->value}/{$comment->id()}",
 -        'href' => "comment/reply/{$comment->nid->target_id}/{$comment->id()}",
++        'href' => "comment/reply/{$comment->entity_type->value}/{$comment->entity_id->target_id}/{$comment->field_name->value}/{$comment->id()}",
          'html' => TRUE,
        );
        if ($comment->status->value == COMMENT_NOT_PUBLISHED) {
@@@ -998,7 -967,7 +998,7 @@@
        }
        $links['comment-reply'] = array(
          'title' => t('reply'),
-         'href' => "comment/reply/{$comment->entity_type->value}/{$comment->entity_id->value}/{$comment->field_name->value}/{$comment->id()}",
 -        'href' => "comment/reply/{$comment->nid->target_id}/{$comment->id()}",
++        'href' => "comment/reply/{$comment->entity_type->value}/{$comment->entity_id->target_id}/{$comment->field_name->value}/{$comment->id()}",
          'html' => TRUE,
        );
      }
@@@ -1552,11 -1574,11 +1552,11 @@@ function comment_preview(Comment $comme
      $preview_build['comment_preview'] = $comment_build;
    }
  
-   if ($comment->pid->value) {
+   if ($comment->pid->target_id) {
      $build = array();
 -    $comment = $comment->pid->entity;
 -    if ($comment && $comment->status->value == COMMENT_PUBLISHED) {
 -      $build = comment_view($comment);
 +    $parent = $comment->pid->entity;
 +    if ($parent && $parent->status->value == COMMENT_PUBLISHED) {
 +      $build = comment_view($parent);
      }
    }
    else {
@@@ -1608,9 -1625,9 +1608,9 @@@ function comment_prepare_author(Commen
   */
  function template_preprocess_comment(&$variables) {
    $comment = $variables['elements']['#comment'];
-   $comment_entity = entity_load($comment->entity_type->value, $comment->entity_id->value);
 -  $node = $variables['elements']['#node'];
++  $comment_entity = entity_load($comment->entity_type->value, $comment->entity_id->target_id);
    $variables['comment'] = $comment;
 -  $variables['node'] = $node;
 +  $variables['comment_entity'] = $comment_entity;
  
    $account = comment_prepare_author($comment);
    $variables['author'] = theme('username', array('account' => $account));
@@@ -1705,11 -1722,10 +1705,11 @@@
      $variables['attributes']['class'][] = 'by-anonymous';
    }
    else {
-     if (($comment_entity instanceof EntityNG && !empty($comment_entity->uid->value) && $comment->uid->value == $comment_entity->uid->value) ||
-         (!empty($comment_entity->uid) && $comment->uid->value == $comment_entity->uid)) {
 -    if ($comment->uid->target_id == $variables['node']->uid) {
 -      $variables['attributes']['class'][] = 'by-node-author';
++    if (($comment_entity instanceof EntityNG && !empty($comment_entity->uid->target_id) && $comment->uid->target_id == $comment_entity->uid->target_id) ||
++        (!empty($comment_entity->uid) && $comment->uid->target_id == $comment_entity->uid)) {
 +      $variables['attributes']['class'][] = 'by-' . $comment_entity->entityType() . '-author';
      }
-     if ($comment->uid->value == $variables['user']->uid) {
+     if ($comment->uid->target_id == $variables['user']->uid) {
        $variables['attributes']['class'][] = 'by-viewer';
      }
    }
diff --cc core/modules/comment/comment.pages.inc
index 6cfa72e,da359a4..0000000
--- a/core/modules/comment/comment.pages.inc
+++ b/core/modules/comment/comment.pages.inc
@@@ -69,14 -59,12 +69,14 @@@ function comment_reply(Drupal\Core\Enti
          if ($comment->status->value == COMMENT_PUBLISHED) {
            // If that comment exists, make sure that the current comment and the
            // parent comment both belong to the same parent node.
-           if ($comment->entity_id->value != $entity->id() ||
 -          if ($comment->nid->target_id != $node->nid) {
 -            // Attempting to reply to a comment not belonging to the current nid.
++          if ($comment->entity_id->target_id != $entity->id() ||
 +              $comment->field_name->value != $field_name ||
 +              $comment->entity_type->value != $entity->entityType()) {
 +            // Attempting to reply to a comment not belonging to the current entity.
              drupal_set_message(t('The comment you are replying to does not exist.'), 'error');
 -            drupal_goto("node/$node->nid");
 +            drupal_goto($uri['path']);
            }
 -          // Display the parent comment
 +          // Display the parent comment.
            $build['comment_parent'] = comment_view($comment);
          }
          else {
diff --cc core/modules/comment/comment.tokens.inc
index d17f523,715b63d..0000000
--- a/core/modules/comment/comment.tokens.inc
+++ b/core/modules/comment/comment.tokens.inc
@@@ -182,9 -175,9 +182,9 @@@ function comment_tokens($type, $tokens
            break;
  
          case 'parent':
-           if (!empty($comment->pid->value)) {
-             $parent = comment_load($comment->pid->value);
+           if (!empty($comment->pid->target_id)) {
 -            $parent = comment_load($comment->pid->target_id);
 -            $replacements[$original] = $sanitize ? filter_xss($parent->subject) : $parent->subject;
++            $parent = entity_load('comment', $comment->pid->target_id);
 +            $replacements[$original] = $sanitize ? filter_xss($parent->subject->value) : $parent->subject->value;
            }
            break;
  
@@@ -196,33 -189,17 +196,33 @@@
            $replacements[$original] = format_date($comment->changed->value, 'medium', '', NULL, $langcode);
            break;
  
 -        case 'node':
 -          $node = $comment->nid->entity;
 -          $title = $node->label();
 +        case 'entity':
-           $entity = entity_load($comment->entity_type->value, $comment->entity_id->value);
++          $entity = entity_load($comment->entity_type->value, $comment->entity_id->target_id);
 +          $title = $entity->label();
            $replacements[$original] = $sanitize ? filter_xss($title) : $title;
            break;
 +
 +        case 'node':
 +          if ($comment->entity_type->value == 'node') {
-             $entity = entity_load($comment->entity_type->value, $comment->entity_id->value);
++            $entity = entity_load($comment->entity_type->value, $comment->entity_id->target_id);
 +            $title = $entity->label();
 +            $replacements[$original] = $sanitize ? filter_xss($title) : $title;
 +          }
 +          else {
 +            $replacements[$original] = NULL;
 +          }
 +          break;
        }
      }
  
      // Chained token relationships.
 -    if ($node_tokens = token_find_with_prefix($tokens, 'node')) {
 -      $node = $comment->nid->entity;
 +    if ($entity_tokens = token_find_with_prefix($tokens, 'entity')) {
-       $entity = entity_load($comment->entity_type->value, $comment->entity_id->value);
++      $entity = entity_load($comment->entity_type->value, $comment->entity_id->target_id);
 +      $replacements += token_generate($comment->entity_type->value, $entity_tokens, array($comment->entity_type->value => $entity), $options);
 +    }
 +
 +    if (($node_tokens = token_find_with_prefix($tokens, 'node')) && $comment->entity_type->value == 'node') {
-       $node = entity_load($comment->entity_type->value, $comment->entity_id->value);
++      $node = entity_load($comment->entity_type->value, $comment->entity_id->target_id);
        $replacements += token_generate('node', $node_tokens, array('node' => $node), $options);
      }
  
diff --cc core/modules/comment/lib/Drupal/comment/CommentRenderController.php
index 6e61777,dab8dc4..0000000
--- a/core/modules/comment/lib/Drupal/comment/CommentRenderController.php
+++ b/core/modules/comment/lib/Drupal/comment/CommentRenderController.php
@@@ -37,27 -37,22 +37,27 @@@ class CommentRenderController extends E
  
      parent::buildContent($entities, $displays, $view_mode, $langcode);
  
 -    // Load all nodes of all comments at once.
 -    $nids = array();
 +    // Load all entities of all comments at once.
 +    $comment_entity_ids = array();
 +    $comment_entities = array();
      foreach ($entities as $entity) {
-       $comment_entity_ids[$entity->entity_type->value][] = $entity->entity_id->value;
 -      $nids[$entity->nid->target_id] = $entity->nid->target_id;
++      $comment_entity_ids[$entity->entity_type->value][] = $entity->entity_id->target_id;
 +    }
 +    // Load entities in bulk, this is more performant than using
 +    // $comment->entity_id->value as we can load them in bulk per-type.
 +    foreach ($comment_entity_ids as $entity_type => $entity_ids) {
 +      $comment_entities[$entity_type] = entity_load_multiple($entity_type, $entity_ids);
      }
 -    $nodes = node_load_multiple($nids);
  
      foreach ($entities as $entity) {
-       if (isset($comment_entities[$entity->entity_type->value][$entity->entity_id->value])) {
-         $comment_entity = $comment_entities[$entity->entity_type->value][$entity->entity_id->value];
 -      if (isset($nodes[$entity->nid->target_id])) {
 -        $node = $nodes[$entity->nid->target_id];
++      if (isset($comment_entities[$entity->entity_type->value][$entity->entity_id->target_id])) {
++        $comment_entity = $comment_entities[$entity->entity_type->value][$entity->entity_id->target_id];
        }
        else {
 -        throw new \InvalidArgumentException(t('Invalid node for comment.'));
 +        throw new \InvalidArgumentException(t('Invalid entity for comment.'));
        }
 -      $entity->content['#node'] = $node;
 -      $entity->content['#theme'] = 'comment__node_' . $node->bundle();
 +      $entity->content['#entity'] = $entity;
 +      $entity->content['#theme'] = 'comment__' . $entity->entity_type->value . '__' . $comment_entity->bundle() . '__' . $entity->field_name->value;
        $entity->content['links'] = array(
          '#theme' => 'links__comment',
          '#pre_render' => array('drupal_pre_render_links'),
diff --cc core/modules/comment/lib/Drupal/comment/CommentStorageController.php
index 03db901,6851be0..0000000
--- a/core/modules/comment/lib/Drupal/comment/CommentStorageController.php
+++ b/core/modules/comment/lib/Drupal/comment/CommentStorageController.php
@@@ -72,16 -91,10 +72,16 @@@ class CommentStorageController extends 
            // is extended in a faulty manner.
            throw new LogicException('preSave is called again without calling postSave() or releaseThreadLock()');
          }
-         if ($comment->pid->value == 0) {
+         if ($comment->pid->target_id == 0) {
            // This is a comment with no parent comment (depth 0): we start
            // by retrieving the maximum thread level.
 -          $max = db_query('SELECT MAX(thread) FROM {comment} WHERE nid = :nid', array(':nid' => $comment->nid->target_id))->fetchField();
 +          $query = db_select('comment', 'c')
-             ->condition('entity_id', $comment->entity_id->value)
++            ->condition('entity_id', $comment->entity_id->target_id)
 +            ->condition('field_name', $comment->field_name->value)
 +            ->condition('entity_type', $comment->entity_type->value);
 +          $query->addExpression('MAX(thread)', 'thread');
 +          $max = $query->execute()
 +            ->fetchField();
            // Strip the "/" from the end of the thread.
            $max = rtrim($max, '/');
            // We need to get the value at the correct depth.
@@@ -98,14 -112,10 +98,14 @@@
            $parent->thread->value = (string) rtrim((string) $parent->thread->value, '/');
            $prefix = $parent->thread->value . '.';
            // Get the max value in *this* thread.
 -          $max = db_query("SELECT MAX(thread) FROM {comment} WHERE thread LIKE :thread AND nid = :nid", array(
 -            ':thread' => $parent->thread->value . '.%',
 -            ':nid' => $comment->nid->target_id,
 -          ))->fetchField();
 +          $query = db_select('comment', 'c')
-             ->condition('entity_id', $comment->entity_id->value)
++            ->condition('entity_id', $comment->entity_id->target_id)
 +            ->condition('field_name', $comment->field_name->value)
 +            ->condition('entity_type', $comment->entity_type->value)
 +            ->condition('thread', $parent->thread->value . '.%', 'LIKE');
 +          $query->addExpression('MAX(thread)', 'thread');
 +          $max = $query->execute()
 +            ->fetchField();
  
            if ($max == '') {
              // First child of this parent. As the other two cases do an
@@@ -127,7 -137,7 +127,7 @@@
          // has the lock, just move to the next integer.
          do {
            $thread = $prefix . comment_int_to_alphadecimal(++$n) . '/';
-         } while (!lock()->acquire("comment:{$comment->entity_id->value}:{$comment->entity_type->value}:$thread"));
 -        } while (!lock()->acquire("comment:{$comment->nid->target_id}:$thread"));
++        } while (!lock()->acquire("comment:{$comment->entity_id->target_id}:{$comment->entity_type->value}:$thread"));
          $this->threadLock = $thread;
        }
        if (empty($comment->created->value)) {
@@@ -283,13 -274,14 +283,14 @@@
      $properties['pid'] = array(
        'label' => t('Parent ID'),
        'description' => t('The parent comment ID if this is a reply to a comment.'),
-       'type' => 'entityreference_field',
-       'settings' => array('entity type' => 'comment'),
+       'type' => 'entity_reference_field',
+       'settings' => array('target_type' => 'comment'),
      );
 -    $properties['nid'] = array(
 -      'label' => t('Node ID'),
 -      'description' => t('The ID of the node of which this comment is a reply.'),
 +    $properties['entity_id'] = array(
 +      'label' => t('Entity ID'),
 +      'description' => t('The ID of the entity of which this comment is a reply.'),
-       'type' => 'integer_field',
+       'type' => 'entity_reference_field',
+       'settings' => array('target_type' => 'node'),
        'required' => TRUE,
      );
      $properties['langcode'] = array(
diff --cc core/modules/comment/lib/Drupal/comment/FieldNewValue.php
index 9734f4b,52875ca..0000000
--- a/core/modules/comment/lib/Drupal/comment/FieldNewValue.php
+++ b/core/modules/comment/lib/Drupal/comment/FieldNewValue.php
diff --cc core/modules/comment/lib/Drupal/comment/Tests/CommentInterfaceTest.php
index 200dc92,24a7931..0000000
--- a/core/modules/comment/lib/Drupal/comment/Tests/CommentInterfaceTest.php
+++ b/core/modules/comment/lib/Drupal/comment/Tests/CommentInterfaceTest.php
@@@ -92,24 -92,13 +92,24 @@@ class CommentInterfaceTest extends Comm
      $reply = $this->postComment(NULL, $this->randomName(), '', TRUE);
      $reply_loaded = comment_load($reply->id());
      $this->assertTrue($this->commentExists($reply, TRUE), 'Reply found.');
-     $this->assertEqual($comment->id(), $reply_loaded->pid->value, 'Pid of a reply to a comment is set correctly.');
+     $this->assertEqual($comment->id(), $reply_loaded->pid->target_id, 'Pid of a reply to a comment is set correctly.');
 -    $this->assertEqual(rtrim($comment->thread->value, '/') . '.00/', $reply_loaded->thread->value, 'Thread of reply grows correctly.');
 +    // Check the thread of reply grows correctly.
 +    $this->assertEqual(rtrim($comment->thread->value, '/') . '.00/', $reply_loaded->thread->value);
  
 -    // Second reply to comment #3 creating comment #4.
 -    $this->drupalGet('comment/reply/' . $this->node->nid . '/' . $comment->id());
 -    $this->assertText($subject_text, 'Individual comment-reply subject found.');
 -    $this->assertText($comment_text, 'Individual comment-reply body found.');
 +    // Second reply to comment #2 creating comment #4.
 +    $this->drupalGet('comment/reply/node/' . $this->node->nid . '/comment/' . $comment->id());
 +    $this->assertText($comment->subject->value, 'Individual comment-reply subject found.');
 +    $this->assertText($comment->comment_body->value, 'Individual comment-reply body found.');
 +    $reply = $this->postComment(NULL, $this->randomName(), $this->randomName(), TRUE);
 +    $reply_loaded = comment_load($reply->id());
 +    $this->assertTrue($this->commentExists($reply, TRUE), 'Second reply found.');
 +    // Check the thread of second reply grows correctly.
 +    $this->assertEqual(rtrim($comment->thread->value, '/') . '.01/', $reply_loaded->thread->value);
 +
 +    // Reply to comment #4 creating comment #5.
 +    $this->drupalGet('comment/reply/node/' . $this->node->nid . '/comment/' . $reply_loaded->id());
 +    $this->assertText($reply_loaded->subject->value, 'Individual comment-reply subject found.');
 +    $this->assertText($reply_loaded->comment_body->value, 'Individual comment-reply body found.');
      $reply = $this->postComment(NULL, $this->randomName(), $this->randomName(), TRUE);
      $reply_loaded = comment_load($reply->id());
      $this->assertTrue($this->commentExists($reply, TRUE), 'Second reply found.');
diff --cc core/modules/comment/lib/Drupal/comment/Tests/CommentTokenReplaceTest.php
index 956388e,6bcc992..0000000
--- a/core/modules/comment/lib/Drupal/comment/Tests/CommentTokenReplaceTest.php
+++ b/core/modules/comment/lib/Drupal/comment/Tests/CommentTokenReplaceTest.php
@@@ -61,11 -61,11 +61,11 @@@ class CommentTokenReplaceTest extends C
      $tests['[comment:edit-url]'] = url('comment/' . $comment->id() . '/edit', $url_options);
      $tests['[comment:created:since]'] = format_interval(REQUEST_TIME - $comment->created->value, 2, $language_interface->langcode);
      $tests['[comment:changed:since]'] = format_interval(REQUEST_TIME - $comment->changed->value, 2, $language_interface->langcode);
-     $tests['[comment:parent:cid]'] = $comment->pid->value;
+     $tests['[comment:parent:cid]'] = $comment->pid->target_id;
      $tests['[comment:parent:title]'] = check_plain($parent_comment->subject->value);
-     $tests['[comment:node:nid]'] = $comment->entity_id->value;
 -    $tests['[comment:node:nid]'] = $comment->nid->target_id;
++    $tests['[comment:node:nid]'] = $comment->entity_id->target_id;
      $tests['[comment:node:title]'] = check_plain($node->title);
-     $tests['[comment:author:uid]'] = $comment->uid->value;
+     $tests['[comment:author:uid]'] = $comment->uid->target_id;
      $tests['[comment:author:name]'] = check_plain($this->admin_user->name);
  
      // Test to make sure that we generated something for each token.
diff --cc core/modules/comment/lib/Drupal/comment/Tests/Views/DefaultViewRecentComments.php
index d1383a1,3006f94..0000000
--- a/core/modules/comment/lib/Drupal/comment/Tests/Views/DefaultViewRecentComments.php
+++ b/core/modules/comment/lib/Drupal/comment/Tests/Views/DefaultViewRecentComments.php
@@@ -72,22 -71,15 +72,22 @@@ class DefaultViewRecentComments extend
      // Add a node of the new content type.
      $node_data = array(
        'type' => $content_type->type,
 +      "comment[$language_not_specified][0][comment]" => COMMENT_OPEN
      );
  
 +    comment_add_default_comment_field('node', $content_type->type);
      $this->node = $this->drupalCreateNode($node_data);
  
 +    views_invalidate_cache();
 +
      // Create some comments and attach them to the created node.
      for ($i = 0; $i < $this->masterDisplayResults; $i++) {
 -      $comment = entity_create('comment', array('node_type' => 'comment_node_' . $this->node->type));
 +      $comment = entity_create('comment', array('field_name' => 'comment'));
-       $comment->uid->value = 0;
+       $comment->uid->target_id = 0;
 -      $comment->nid->target_id = $this->node->nid;
 +      $comment->entity_type->value = 'node';
 +      // Stagger the comments so the timestamp sorting works.
 +      $comment->created->value = REQUEST_TIME - $i;
-       $comment->entity_id->value = $this->node->nid;
++      $comment->entity_id->target_id = $this->node->nid;
        $comment->subject->value = 'Test comment ' . $i;
        $comment->comment_body->value = 'Test body ' . $i;
        $comment->comment_body->format = 'full_html';
@@@ -115,7 -107,7 +115,7 @@@
      );
      $expected_result = array();
      foreach (array_values($this->commentsCreated) as $key => $comment) {
-       $expected_result[$key]['entity_id'] = $comment->entity_id->value;
 -      $expected_result[$key]['nid'] = $comment->nid->target_id;
++      $expected_result[$key]['entity_id'] = $comment->entity_id->target_id;
        $expected_result[$key]['subject'] = $comment->subject->value;
        $expected_result[$key]['cid'] = $comment->id();
        $expected_result[$key]['changed'] = $comment->changed->value;
@@@ -147,7 -139,7 +147,7 @@@
      );
      $expected_result = array();
      foreach (array_values($this->commentsCreated) as $key => $comment) {
-       $expected_result[$key]['entity_id'] = $comment->entity_id->value;
 -      $expected_result[$key]['nid'] = $comment->nid->target_id;
++      $expected_result[$key]['entity_id'] = $comment->entity_id->target_id;
        $expected_result[$key]['subject'] = $comment->subject->value;
        $expected_result[$key]['changed'] = $comment->changed->value;
        $expected_result[$key]['created'] = $comment->created->value;
diff --cc core/modules/forum/forum.module
index 04efecb,872eb95..0000000
--- a/core/modules/forum/forum.module
+++ b/core/modules/forum/forum.module
@@@ -486,9 -486,7 +486,9 @@@ function forum_taxonomy_term_delete(Ter
   * comment_save() calls hook_comment_publish() for all published comments.
   */
  function forum_comment_publish($comment) {
 -  _forum_update_forum_index($comment->nid->target_id);
 +  if ($comment->entity_type->value == 'node') {
-     _forum_update_forum_index($comment->entity_id->value);
++    _forum_update_forum_index($comment->entity_id->target_id);
 +  }
  }
  
  /**
@@@ -500,8 -498,8 +500,8 @@@
  function forum_comment_update($comment) {
    // comment_save() calls hook_comment_publish() for all published comments,
    // so we need to handle all other values here.
 -  if (!$comment->status->value) {
 -    _forum_update_forum_index($comment->nid->target_id);
 +  if (!$comment->status->value && $comment->entity_type->value == 'node') {
-     _forum_update_forum_index($comment->entity_id->value);
++    _forum_update_forum_index($comment->entity_id->target_id);
    }
  }
  
@@@ -509,18 -507,14 +509,18 @@@
   * Implements hook_comment_unpublish().
   */
  function forum_comment_unpublish($comment) {
 -  _forum_update_forum_index($comment->nid->target_id);
 +  if ($comment->entity_type->value == 'node') {
-     _forum_update_forum_index($comment->entity_id->value);
++    _forum_update_forum_index($comment->entity_id->target_id);
 +  }
  }
  
  /**
   * Implements hook_comment_delete().
   */
  function forum_comment_delete($comment) {
 -  _forum_update_forum_index($comment->nid->target_id);
 +  if ($comment->entity_type->value == 'node') {
-     _forum_update_forum_index($comment->entity_id->value);
++    _forum_update_forum_index($comment->entity_id->target_id);
 +  }
  }
  
  /**
diff --cc core/modules/rdf/rdf.module
index a6e5e11,255fc97..0000000
--- a/core/modules/rdf/rdf.module
+++ b/core/modules/rdf/rdf.module
@@@ -417,11 -417,9 +417,11 @@@ function rdf_comment_load($comments) 
      // isn't needed until rdf_preprocess_comment() is called, but set it here
      // to optimize performance for websites that implement an entity cache.
      $comment->rdf_data['date'] = rdf_rdfa_attributes($comment->rdf_mapping['created'], $comment->created->value);
-     $entity = entity_load($comment->entity_type->value, $comment->entity_id->value);
 -    $comment->rdf_data['nid_uri'] = url('node/' . $comment->nid->target_id);
 -    if ($comment->pid->target_id) {
++    $entity = entity_load($comment->entity_type->value, $comment->entity_id->target_id);
 +    $uri = $entity->uri();
 +    $comment->rdf_data['entity_uri'] = url($uri['path'], $uri['options']);
 +    if ($comment->pid->value) {
-       $comment->rdf_data['pid_uri'] = url('comment/' . $comment->pid->value, array('fragment' => 'comment-' . $comment->pid->value));
+       $comment->rdf_data['pid_uri'] = url('comment/' . $comment->pid->target_id, array('fragment' => 'comment-' . $comment->pid->target_id));
      }
    }
  }
@@@ -741,18 -735,18 +741,18 @@@ function rdf_preprocess_comment(&$varia
      $variables['title_attributes']['datatype'] = '';
    }
  
 -  // Annotates the parent relationship between the current comment and the node
 -  // it belongs to. If available, the parent comment is also annotated.
 +  // Annotates the parent relationship between the current comment and the
 +  // entity it belongs to. If available, the parent comment is also annotated.
    if (!empty($comment->rdf_mapping['pid'])) {
 -    // Adds the relation to the parent node.
 -    $parent_node_attributes['rel'] = $comment->rdf_mapping['pid']['predicates'];
 -    // The parent node URI is precomputed as part of the rdf_data so that it can
 +    // Adds the relation to the parent entity.
 +    $parent_entity_attributes['rel'] = $comment->rdf_mapping['pid']['predicates'];
 +    // The parent entity URI is precomputed as part of the rdf_data so that it can
      // be cached as part of the entity.
 -    $parent_node_attributes['resource'] = $comment->rdf_data['nid_uri'];
 -    $variables['rdf_metadata_attributes'][] = $parent_node_attributes;
 +    $parent_entity_attributes['resource'] = $comment->rdf_data['entity_uri'];
 +    $variables['rdf_metadata_attributes'][] = $parent_entity_attributes;
  
      // Adds the relation to parent comment, if it exists.
-     if ($comment->pid->value != 0) {
+     if ($comment->pid->target_id != 0) {
        $parent_comment_attributes['rel'] = $comment->rdf_mapping['pid']['predicates'];
        // The parent comment URI is precomputed as part of the rdf_data so that
        // it can be cached as part of the entity.
diff --cc core/modules/search/search.module
index de26282,5c67997..0000000
--- a/core/modules/search/search.module
+++ b/core/modules/search/search.module
@@@ -815,9 -810,7 +815,9 @@@ function search_node_update(Node $node
   */
  function search_comment_insert($comment) {
    // Reindex the node when comments are added.
 -  search_touch_node($comment->nid->target_id);
 +  if ($comment->entity_type->value == 'node') {
-     search_touch_node($comment->entity_id->value);
++    search_touch_node($comment->entity_id->target_id);
 +  }
  }
  
  /**
@@@ -825,9 -818,7 +825,9 @@@
   */
  function search_comment_update($comment) {
    // Reindex the node when comments are changed.
 -  search_touch_node($comment->nid->target_id);
 +  if ($comment->entity_type->value == 'node') {
-     search_touch_node($comment->entity_id->value);
++    search_touch_node($comment->entity_id->target_id);
 +  }
  }
  
  /**
@@@ -835,9 -826,7 +835,9 @@@
   */
  function search_comment_delete($comment) {
    // Reindex the node when comments are deleted.
 -  search_touch_node($comment->nid->target_id);
 +  if ($comment->entity_type->value == 'node') {
-     search_touch_node($comment->entity_id->value);
++    search_touch_node($comment->entity_id->target_id);
 +  }
  }
  
  /**
@@@ -845,9 -834,7 +845,9 @@@
   */
  function search_comment_publish($comment) {
    // Reindex the node when comments are published.
 -  search_touch_node($comment->nid->target_id);
 +  if ($comment->entity_type->value == 'node') {
-     search_touch_node($comment->entity_id->value);
++    search_touch_node($comment->entity_id->target_id);
 +  }
  }
  
  /**
@@@ -855,9 -842,7 +855,9 @@@
   */
  function search_comment_unpublish($comment) {
    // Reindex the node when comments are unpublished.
 -  search_touch_node($comment->nid->target_id);
 +  if ($comment->entity_type->value == 'node') {
-     search_touch_node($comment->entity_id->value);
++    search_touch_node($comment->entity_id->target_id);
 +  }
  }
  
  /**
diff --cc core/modules/system/system.module
index 4f1d49f,322e416..0000000
--- a/core/modules/system/system.module
+++ b/core/modules/system/system.module
diff --cc core/modules/tracker/tracker.module
index 8280f3d,30a0dbb..0000000
--- a/core/modules/tracker/tracker.module
+++ b/core/modules/tracker/tracker.module
@@@ -231,8 -229,8 +231,8 @@@ function tracker_node_predelete(Node $n
  function tracker_comment_update($comment) {
    // comment_save() calls hook_comment_publish() for all published comments
    // so we need to handle all other values here.
 -  if ($comment->status->value != COMMENT_PUBLISHED) {
 -    _tracker_remove($comment->nid->target_id, $comment->uid->target_id, $comment->changed->value);
 +  if ($comment->status->value != COMMENT_PUBLISHED && $comment->entity_type->value == 'node') {
-     _tracker_remove($comment->entity_id->value, $comment->uid->value, $comment->changed->value);
++    _tracker_remove($comment->entity_id->target_id, $comment->uid->target_id, $comment->changed->value);
    }
  }
  
@@@ -243,27 -241,21 +243,27 @@@
   * comment_save() calls hook_comment_publish() for all published comments.
   */
  function tracker_comment_publish($comment) {
 -  _tracker_add($comment->nid->target_id, $comment->uid->target_id, $comment->changed->value);
 +  if ($comment->entity_type->value == 'node') {
-     _tracker_add($comment->entity_id->value, $comment->uid->value, $comment->changed->value);
++    _tracker_add($comment->entity_id->target_id, $comment->uid->target_id, $comment->changed->value);
 +  }
  }
  
  /**
   * Implements hook_comment_unpublish().
   */
  function tracker_comment_unpublish($comment) {
 -  _tracker_remove($comment->nid->target_id, $comment->uid->target_id, $comment->changed->value);
 +  if ($comment->entity_type->value == 'node') {
-     _tracker_remove($comment->entity_id->value, $comment->uid->value, $comment->changed->value);
++    _tracker_remove($comment->entity_id->target_id, $comment->uid->target_id, $comment->changed->value);
 +  }
  }
  
  /**
   * Implements hook_comment_delete().
   */
  function tracker_comment_delete($comment) {
 -  _tracker_remove($comment->nid->target_id, $comment->uid->target_id, $comment->changed->value);
 +  if ($comment->entity_type->value == 'node') {
-     _tracker_remove($comment->entity_id->value, $comment->uid->value, $comment->changed->value);
++    _tracker_remove($comment->entity_id->target_id, $comment->uid->target_id, $comment->changed->value);
 +  }
  }
  
  /**
diff --cc core/modules/views/config/views.view.comments_recent.yml
index d775ad1,6560938..0000000
--- a/core/modules/views/config/views.view.comments_recent.yml
+++ b/core/modules/views/config/views.view.comments_recent.yml
@@@ -30,11 -30,11 +30,12 @@@ display
          options:
            items_per_page: 5
        relationships:
 -        nid:
 -          id: nid
 +        node:
 +          field: node
 +          id: node
 +          required: '1'
            table: comment
 -          field: nid
+           plugin_id: standard
        fields:
          subject:
            id: subject
@@@ -59,8 -62,9 +63,9 @@@
            id: status_extra
            table: node
            field: status_extra
 -          relationship: nid
 +          relationship: node
            group: 0
+           plugin_id: node_status
        style:
          type: html_list
        row:
@@@ -85,9 -89,10 +90,10 @@@
            id: title
            table: node
            field: title
 -          relationship: nid
 +          relationship: node
            label: 'Reply to'
            link_to_node: 1
+           plugin_id: node
          timestamp:
            id: timestamp
            table: comment
diff --cc core/modules/views/tests/views_test_config/test_views/views.view.test_destroy.yml
index 4d1356a,f7df985..0000000
--- a/core/modules/views/tests/views_test_config/test_views/views.view.test_destroy.yml
+++ b/core/modules/views/tests/views_test_config/test_views/views.view.test_destroy.yml
@@@ -116,29 -131,34 +131,34 @@@ display
        query:
          type: views_query
        relationships:
 -        cid:
 -          field: cid
 -          id: cid
 +        comment_cid:
 +          field: comment_cid
 +          id: comment_cid
            table: node
+           plugin_id: standard
          pid:
            field: pid
            id: pid
            table: comment
 -          relationship: cid
 +          relationship: comment_cid
+           plugin_id: standard
          uid:
            field: uid
            id: uid
            table: comment
 -          relationship: cid
 +          relationship: comment_cid
+           plugin_id: standard
        sorts:
          last_comment_name:
            field: last_comment_name
            id: last_comment_name
 -          table: node_comment_statistics
 -          plugin_id: comment_ncs_last_comment_name
 +          table: comment_entity_statistics
++          plugin_id: comment_ces_last_comment_name
          last_comment_timestamp:
            field: last_comment_timestamp
            id: last_comment_timestamp
 -          table: node_comment_statistics
 +          table: comment_entity_statistics
+           plugin_id: date
        style:
          type: default
        row:
diff --cc core/modules/views/tests/views_test_config/test_views/views.view.test_field_get_entity.yml
index db9db1e,2951397..0000000
--- a/core/modules/views/tests/views_test_config/test_views/views.view.test_field_get_entity.yml
+++ b/core/modules/views/tests/views_test_config/test_views/views.view.test_field_get_entity.yml
@@@ -20,7 -21,8 +21,8 @@@ display
            field: nid
            id: nid
            table: node
 -          relationship: nid
 +          relationship: node
+           plugin_id: node
          uid:
            field: uid
            id: uid
@@@ -35,20 -38,22 +38,22 @@@
        query:
          type: views_query
        relationships:
 -        nid:
 -          field: nid
 -          id: nid
 +        node:
 +          field: node
 +          id: node
            required: '1'
            table: comment
+           plugin_id: standard
          uid:
            admin_label: ''
            field: uid
            group_type: group
            id: uid
            label: author
 -          relationship: nid
 +          relationship: node
            required: '0'
            table: node
+           plugin_id: standard
        sorts: {  }
        style:
          type: default
diff --cc core/modules/views/tests/views_test_config/test_views/views.view.test_handler_relationships.yml
index 94fc786,efa8ccc..0000000
--- a/core/modules/views/tests/views_test_config/test_views/views.view.test_handler_relationships.yml
+++ b/core/modules/views/tests/views_test_config/test_views/views.view.test_handler_relationships.yml
@@@ -10,16 -10,19 +10,19 @@@ display
            id: title
            table: node
            field: title
+           plugin_id: node
        relationships:
 -        cid:
 -          id: cid
 +        comment_cid:
 +          id: comment_cid
            table: node
 -          field: cid
 +          field: comment_cid
+           plugin_id: standard
          nid:
            id: nid
            table: comment
 -          field: nid
 -          relationship: cid
 +          field: node
 +          relationship: comment_cid
+           plugin_id: standard
      display_plugin: default
      display_title: Master
      id: default
diff --git a/core/modules/comment/lib/Drupal/comment/CommentFormController.php b/core/modules/comment/lib/Drupal/comment/CommentFormController.php
index ff7d2d3..dbddcb1 100644
--- a/core/modules/comment/lib/Drupal/comment/CommentFormController.php
+++ b/core/modules/comment/lib/Drupal/comment/CommentFormController.php
@@ -39,8 +39,8 @@ public function form(array $form, array &$form_state, EntityInterface $comment)
 
     // If not replying to a comment, use our dedicated page callback for new
     // comments on entities.
-    if (!$comment->id() && empty($comment->pid->value)) {
-      $form['#action'] = url('comment/reply/' . $comment->entity_type->value . '/' . $comment->entity_id->value . '/' . $comment->field_name->value);
+    if (!$comment->id() && empty($comment->pid->target_id)) {
+      $form['#action'] = url('comment/reply/' . $comment->entity_type->value . '/' . $comment->entity_id->target_id . '/' . $comment->field_name->value);
     }
 
     if (isset($form_state['comment_preview'])) {
@@ -55,7 +55,6 @@ public function form(array $form, array &$form_state, EntityInterface $comment)
       $form['author'] += array(
         '#type' => 'details',
         '#title' => t('Administration'),
-        '#collapsible' => TRUE,
         '#collapsed' => TRUE,
       );
     }
@@ -78,38 +77,23 @@ public function form(array $form, array &$form_state, EntityInterface $comment)
     }
 
     // Add the author name field depending on the current user.
+    $form['author']['name'] = array(
+      '#type' => 'textfield',
+      '#title' => t('Your name'),
+      '#default_value' => $author,
+      '#required' => (!$user->uid && $anonymous_contact == COMMENT_ANONYMOUS_MUST_CONTACT),
+      '#maxlength' => 60,
+      '#size' => 30,
+    );
     if ($is_admin) {
-      $form['author']['name'] = array(
-        '#type' => 'textfield',
-        '#title' => t('Authored by'),
-        '#default_value' => $author,
-        '#maxlength' => 60,
-        '#size' => 30,
-        '#description' => t('Leave blank for %anonymous.', array('%anonymous' => config('user.settings')->get('anonymous'))),
-        '#autocomplete_path' => 'user/autocomplete',
-      );
+      $form['author']['name']['#title'] = t('Authored by');
+      $form['author']['name']['#description'] = t('Leave blank for %anonymous.', array('%anonymous' => config('user.settings')->get('anonymous')));
+      $form['author']['name']['#autocomplete_path'] = 'user/autocomplete';
     }
     elseif ($user->uid) {
-      $form['author']['_author'] = array(
-        '#type' => 'item',
-        '#title' => t('Your name'),
-        '#markup' => theme('username', array('account' => $user)),
-      );
-
-      $form['author']['name'] = array(
-        '#type' => 'value',
-        '#value' => $author,
-      );
-    }
-    else {
-      $form['author']['name'] = array(
-        '#type' => 'textfield',
-        '#title' => t('Your name'),
-        '#default_value' => $author,
-        '#required' => (!$user->uid && $anonymous_contact == COMMENT_ANONYMOUS_MUST_CONTACT),
-        '#maxlength' => 60,
-        '#size' => 30,
-      );
+      $form['author']['name']['#type'] = 'item';
+      $form['author']['name']['#value'] = $form['author']['name']['#default_value'];
+      $form['author']['name']['#markup'] = theme('username', array('account' => $user));
     }
 
     // Add author e-mail and homepage fields depending on the current user.
@@ -165,7 +149,7 @@ public function form(array $form, array &$form_state, EntityInterface $comment)
     // Used for conditional validation of author fields.
     $form['is_anonymous'] = array(
       '#type' => 'value',
-      '#value' => ($comment->id() ? !$comment->uid->value : !$user->uid),
+      '#value' => ($comment->id() ? !$comment->uid->target_id : !$user->uid),
     );
 
     // Make the comment inherit the current content language unless specifically
@@ -177,7 +161,8 @@ public function form(array $form, array &$form_state, EntityInterface $comment)
 
     // Add internal comment properties.
     foreach (array('cid', 'pid', 'entity_id', 'entity_type', 'field_name', 'uid', 'langcode') as $key) {
-      $form[$key] = array('#type' => 'value', '#value' => $comment->$key->value);
+      $key_name = key($comment->$key->offsetGet(0)->getProperties());
+      $form[$key] = array('#type' => 'value', '#value' => $comment->$key->{$key_name});
     }
 
     return parent::form($form, $form_state, $comment);
@@ -278,7 +263,7 @@ public function submit(array $form, array &$form_state) {
     // @todo Too fragile. Should be prepared and stored in comment_form()
     // already.
     if (!$comment->is_anonymous && !empty($comment->name->value) && ($account = user_load_by_name($comment->name->value))) {
-      $comment->uid->value = $account->uid;
+      $comment->uid->target_id = $account->uid;
     }
     // If the comment was posted by an anonymous user and no author name was
     // required, use "Anonymous" by default.