As far as I've seen, theres four kinds of forums, with a fifth kind for imageboards.
THeres ones that, generally, have ended up rather reasonable, but not nice all the time
Ones that moderate the crap out of everything and generally are rather boring to read to me because of it
Ones that are RAEG central with a side of calm
Possibly overly-appreciative ones with everything else slightly buried by the worshipping
And imageboads, where nobody gives an f about whatever is going on unless someone is using an actual name.