I'll focus my review on the design.
It's pretty. That's really important. The header is really simple and nice. The menu bars look good BUT the overstate of the buttons look weird. They could get a different color. Content area is nice, white, readable, ok

. The sidebar is also simple but the gradient used in it is to white. The upper part of the letters from the category titles is hard to read like that. As for the footer, I really like it, but you could add a border/dropshadow from the white area of the content area.
Good luck
