Okay, now you're a forum junkie - you just LOVE forums. But you're not going to spend your life posting to every forum in existence. So what is the threshold level? What determines a forum worth your time from one that isn't?
I guess what I'm asking is when you find a new forum (be it via the search engines, another site, etc), what specifically about it makes it worth staying on and posting ... or worth dismissing as just another forum?