Administration features are top notch... I have been using this on some of my own projects, and it rocks.
Again, it in and of itself does not add much featurewise for the end users, but it makes it much easier for me to add them. The frontpage was a snap.. and a couple other additions have already been added... more soon. Chat and Classifieds are more of a priority though.
Skype users should find a new toy in there.

If you use skype, look around your profile...
Some New Features and Improvements: (as you will see, most is back-end stuff)
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* Product/Plugin system with over 550 'hook' locations
strategically placed in the code. Allows modification
and extension of vBulletin without physical alteration
of the vBulletin PHP scripts.
* Inline moderation allows multiple threads or posts to be
have moderation actions performed without a visit to the
admin or moderator control panels
* Completely rewritten message editor with ability to
instantly switch between standard and WYSIWYG modes
* Thread title editing on forumdisplay via AJAX
* Thread opening and closing on forumdisplay via AJAX
* Super-Quick Reply on showthread via AJAX
* Inline post edit on showthread via AJAX
* Username suggestion for PM recipients and search by
user via AJAX
* Data manipulation APIs (Data Manager) for centralized
data saving
* Template History & Comparison for easy tracking of
changes
* Database-based thread and forum read marking
* MySQL Full Text Search
* Additional Datastore Storage Methods
* SMTP Mail Wrapper
* MySQLi Wrapper
* PHPDoc'd Source Code
* Moderator log language abstraction
* Webkit support for style manager color picker
* ImageMagick 6 Support (alternative to GD)
* Calendar events support start/end times
* Custom avatar and profile picture resizing
* Profile pictures can be saved to filesystem
* Statistics ordering
* Each attachment image type can be individually set to
generate thumbnails or not
* Each attachment image type can be individually set to
open in a new window or not
* Moderated posts and threads do not contribute to post
count until approved
* Language chooser in footer
* New bbcode parser now corrects invalid tag nesting to
ensure valid HTML
* New