The color scheme for the forumhome page is unusual, especially the yellow/red/maroon accents. Is there a particular reason you chose those colors?
I'd also get rid of the avatar-like icon in the header which I've circled in red (see below). Visually, it breaks up the header... in fact, when I first saw it, I thought it was an icon that was being rendered in the wrong place.
You've got a good number of forum categories, but since your site seems to be relatively busy, I don't know if it would be worth combining some of them.
- Dan