The edges seem a bit anti-aliased, I think they'd look nicer with feathered edges. The side thing also looks a bit c+p currently, maybe if you blended those two together it would be better.
I know I have the same problem with the text. People with a version of IE below 7 won't be able to correctly view the transparencies.
The top one was made after the lower one, I merely added light because the lower one looked a bit static.