Only one suggestion, I did not check in IE but in FF the css for the location of the tabs need to have it indented a bit more to the right, it is just slightly hanging over that rounded corner so perhaps if it has a margin or px offset add about 5 px or so.
Very nice, simple, colorful yet not toooooo colorful, simple icons and functional with the tabs up top....
Thanks for the response The tabs are needed and loved by all my members, and countless other users who have come accross the community have also complimented them.