Love the overal design layout of the site.
The one word of caution I'd have for you is that the links from your site to other sites currently are being followed by search engines. This will create a nightmare for you when it comes to Spammers. An online forum with free "link juice" - sign me up!!!!
So I'd recommend that you make any links outside of your domain are flagged as "rel=nofollow". While it won't eliminate spam, it would certainly ensure you're not on a "dofollow" blog list of places to spam from.