Iv been apart of a few and i feel this site can be so much more (our guild wars side that is). I was reading up on what makes a good forum and fell across this:
As a forum administrator, traffic and forum members' participation must be your goal. Yet after people reach your forum, there's still a long way to go to get more registered members and to make your forum active. Here I'd like to share some tips on how to attract people to join your forum and how to make them active in your forum.
1. The forum should basically fan, say, the forum should be based on like-minded people, e.g. Apple fans, iPhone users, movie/music lovers, freebie or freeware lovers, etc. The same interest can appeal people to participate in the forum discussion and help you get more registered members.
2. Start conversation with yourself at the very beginning. People do not join forums which are less active. So for a new forum, you need to create some accounts for yourself and frequently post there. That's very important to attract people to register as your forum member and lead them to post in the forum.
3. The forum admin should take initiative to post interesting threads to make forum active. Taking time to write some controversial/discussible/interesting topics (make sure not too racist) will help you attract more people to your forum and to share their opinions.
4. Advertise your forum on other similar forums. You can post your forum link to other forums, or you can even add the link to your signature then let it be known to others. This is a direct way to lead people to your forum and then to register as a member, as long as the threads are interesting enough. Pay attention that some forums don't allowed users to spam.
5. Launch contest and reward your active members. To make your forum more active, you can start some contests or giveaway. You needn't to give away money. Actually, some websites and companies provide free products to their partners for contest and giveaway. Here is one example:
http://www.winxdvd.com/win-free-copy/. Of course, there're still dozens of such websites that free sponsor products. My point is, contest is an effective way to make your forum more active.