Good news, bad news.
Good news: I'm dying to use Drupal more extensively and have installed and configured test sites on three servers and worked through a number of newbie and eccentric application issues. I like the system very much.
Bad news: the feature write up on permissions as well as the detailed information needs a more explicit warning or statement that Drupal in its current incarnation does *not* support what most people think of a group and individual access permissions to limit access to pages, nodes, or other taxonomic elements.
I'm stupid and didn't check this out thoroughly enough, and am now facing a decision to drop Drupal completely, or try to install multiple db's and instances of it, not a good option except for very simple installations where you only have one group that needs special content not available to other groups.
I see discussions about adding more granular permissions access options, which is great. Many people who work with Windows and Linux systems assume (...and I realize the ass that makes me ;-)) that a 4.0 system release will have basic content access permissions, particularly when you read about role permissions in the feature write-up.
Every site I work on except for completely public sites, requires access permissions to limit and grant access to specialized or 'confidential' content. My understanding is that the current roles really only provide for a variety of administrators and moderators not *content* access permissions.