Hey,
Great design, as many have mentioned the curve at the top of the design replicating the curves on a XBOX 360 is great.
The only suggestions I have for you is to work on your navigation. Light grey text on a dark grey background doesn't go so well. Try working on the color a little. Black & White, Green & White, Green & Yellow, Black & Light Grey, White and Dark Grey some good color combos.
Another thing that you could improve is the font-size of everything. The font's are quite small and upping them by a pixel or two wouldn't hurt.
Overall it's a great design and concept, wish you the best of luck.
Richard