I agree with what Ed has said and additionally think you need to look at all the link colors. For example, lightening the links and the footer color itself would make the Powered By and options links in the footer readable. At the moment the lack of contrast for the links presents a bit of an accessibility issue. I know how time-consuming it can be to get links right for all eventualities across a whole site. You don't necessarily need anything too bright but you will need to test the links when you have a white background, as well as against the blue background.
Given that you have rounded corners for the buttons, and the title image is also curved, the square corners of the top of the main content make it look (for me) a bit odd. I know this wouldn't work for IE but you might want to consider adding -moz-border-radius-topleft:10px and -moz-border-radius-topright:10px - and -webkit-border-radius of course - to soften the corners slightly for those of us on FF and Safari.
I agree with Brunhilda about the ad boxes, particularly the one in the centre at the top of the page. Given that top centre is one of the first places the eye goes to on a site, the ad box in that position slightly takes the focus away from the site itself. That's great for the advertiser but not really what you want.