We opened our poker forum 1 1/2 years ago, now we have 1280+ members, of which only 300 or so are active members. It took a longgggggggggg time and a LOT OF $$$$$$$$$ to get it going.
There’s no trick to it really, just trial and error, it’s very hard to get going, we were just about to give up when we had a few hundred members then all of a sudden google and yahoo decided they loved us and a few weeks later we had a few hundred more etc.
I will tell you now that most forums fail. And we’re just now starting to make money off of it. Most poker forum goers are freeroll hunters and bonus hunters so you have to target those guys, get exclusive freerolls going, eventually you’ll start to pick up the real money players, but over time.