1. Text is too dark -- little readibility.
2. Double gallery -- duplicity that loses focus (what are you trying to grab the viewer attention with? The top or bottom gallery, or the wide ads on the right?).
3. At the net standard resolution of 1024x768: all I see is a too dark registration message; and corner of the ads on the right.
4. Scrollbar and the forum itself isn't liquid but fixed.
Few folks have the 1280x1024 or 1440x960 resolutions to properly view your site. Many gamers use the 1024x768 resolution LCDs now (just plain cheaper).
Can't stress enough with a liquid layout, especially if you want to please both the largest viewership and those with higher res monitors.