major-_-turnon - 2008-10-13 related videos: LBP: Moderating Penis Levels
fluffy - 2008-11-03 LBP has pretty simple community moderation. If you see something objectionable you just press Select and it pops up a griefing report screen, which then gets reviewed by someone.
I don't know what the disincentive is though. Even if your PSN account gets banned I don't know how they'd prevent you from just setting up a new one (although if you start having to juggle multiple accounts to deal with DLC it might get frustrating and possibly expensive for the griefers).