matt3o wrote: I'm afraid Bayesian would add more work (dealing with false positives mostly)
Perhaps; it could always be pre-trained on the current message corpus first though.
Also, we are mostly talking about first posts by fresh users I assume? Most often starting a new topic for that message as well?
How many in a day/week are we talking about? Could the "report this message" button be smartened up with logic to nuke fresh accounts when some set of reliable/established members report a message?