I don't think there are any issues related to placement, but based on what I can see, your site has no real content. All pages consist of links, and the only content available is on other sites (via the links). You may want to add at least some content, especially in your home page, to assure that you're in compliance with the ToS. HTH, Sam
WebFreedom is right. I would confirm your site with google (or was your account accepted for this site? Then you should be fine) if it is against their ToS. Anyway very nice blending work. On top links and popular link your ads have a border. I would remove it because it blends in more nicely