[malfhok]

This is a quick fix for now, until bbPress gets the well needed mass-edit:

If you have your bbPress integrated with your WordPress, then all of the bozo users will show up with no role in your WP users mass-edit. You can mass delete them from there. Look out, though, because non-activated accounts show up with no role as well. I’d check in bbPress for bozos and then delete them in WP after you know who they are.