I just started a new forum http://www.sonicvariable.com/forums/ and i am looking for some input on how to make it run, how to make money, how to get people to start posting, how to get others to promote the site for me.
It looks like you have alot of activity going in "The lounge" section. Your forum stats are impressive. Try the link in my sig. Good Luck.
Get people to post in the other forums, not just "The Lounge", the difference is very large and could put off new members. Use a service such as text-link-ads.com or tnx.net to sell direct text links, adsense doesn't do well on forums. You could also offer a feature allowing members to either donate, or to become a "VIP" or something like that.