stevepavlina.com does seem to be the exception among all the whiny, negativity-spewing forums on the net. Even the arguments here are contained and (usually) purposeful.
I've been on a slight hiatus lately after an intensive research project that landed me on a forum which was very helpful at first, but basically turned out to be a bunch of autistic people who never leave the house but argue incessantly about inconsequential details. I'm kind of recovering from that now.
Forum addiction is still bad, but if you have it, channel it
here