A forum is a great thing if it’s active. Getting it active is tough. Beg your friends to participate, or offer backlinks to people who are willing to agree to make at least a post a day. Some people even sign up for multiple user names and post multiple times to give their forums an active look in order to encourage participation.
Doesn’t hurt to occasionally hold events like chats and poker tournaments in order to keep your forum participants active in the community too.
It’s a long slow process, but I bet if you ask Casinomeister or Winneronline if it’s worth it, they’d tell you, “Hell, yeah.”