I currently use minibb. I have been running my forum for over 5 years and I love some of it's features, absence of which would have made running my forum nightmare.
Here are some features I would like to see in bbpress:
1) Ability to place posts of new users in a moderation queue. Once I approve the users, posts by them will appear.
2) Ability to view/review all the posts/topics since I last checked. Once I check the topics/posts, they'll not be displayed again.