My speed reaing skills need refreshing. Sorry for the wrong take there G_S ..

{walks away, shaking head}

I put in a system a while back for a customer of mine, but for email. Anyone who was deemed semi-authoritative (ie, had an account older than X months/years) could recommend an email address/posting unsuitable. If a given percentage of the total users marked content unsuitable it was removed and put on-hold for a moderator to review.

Nothing's fool-proof, but it seemed to work pretty well.