Current bbPress plugin is very very weak on the mod/admin options.
I would love to see a plugin that would allow threads to be moved between forums (like every other major "forums" product has). Or two entire forums merge together? or merge topics across forums too?
Right now you can only split or merge "topics" within the same forum, you can't move them across forums either. All of these are essential in keeping things clean if users post them in wrong forums...
This is for bbPress 2.x which is as a WP plugin. I think similar things do exist for older bbpress versions.