I don't have a list per se, but I can come up with a few ideas:
AutoQuote
MarkAllRead
Expanded Markup (ie. Underline, Marquee, etc.)
Admin Definable Emoticons (ie. add to a single directory and have the contents displayed for configuration in the Admin CP)
Database Backup/Restore from Admin CP
Improved Moved Thread Handling (ie. Option to leave the thread topic with a link to the moved thread location - Refer to how iKonboard handles thread moves for a better idea on what I mean)
Those are just a few. I'm sure I can come up with some more.
