Hi,
I agree with wullie about making the layout adjust to any resolution. I think it feels very cramped at the moment.
Another point would be to look at the navigation system. There is a graphic based system at the top (with the tabs and so on), and what appears to be a text navigation at the bottom. On closer inspection, the 'text' is actually a graphic too. Is this really necessary? Surely using HTML text with a carefully selected style sheet would give a similar look while giving more benefits to the end user (eg, making the navigation available to more basic browsers, helping those with poor sight adjust the size of it, and, of course, making the page download slightly faster).
The top navigation is ok, but could probably benefit from a little more contrast between the 'selected' tab and the others. As it stands, it's sometimes a little difficult to know where you are in the site. Also, on all pages other than the home page, you should make the logo a link to the home page. This is just one of those things that many people are used to, and it won't affect the design in any way.
On a more positive note, I think it's great that you have stuck to the one color scheme throughout. It gives the site a distinctive look that, hopefully, is consistent with the rest of their visual material. Also, the text is very legible and thankfully hasn't been restricted to the one size. Users with poor eyesight can enlarge the text and the layout remains clear. Just be aware that some of the graphics get moved around slightly when this is done, so that might be something worth looking at.
hth