hmm i like it, nice and clean. makes me think of apple.

The cut away side bit (i presume for a menu or some such) doens't have the inside border right. either there should be a bevel/rounded border on the corresponding middle bit (just like you have at the top between the header and the body) or you should make it a lot tighter and remove the rounded feel from it when corresponding to the centre/body peice.

You should add a backlite to the top bar, i think it looks a tad too plain the way it is with the two highlights. Maybe a reverse bevel to show how the background bar is cut out/integrated with the feature bar.

The end of the top bar appears weird, sorta like you didn't antialis or something, it needs tidying up.

Overall mate a nice concept and i like it.