Hi there!
Your design's pretty solid: it's easily navigated and the colors aren't an eyesore. I would like to suggest however that you consider using a non dark color (white seems to be a good choice) for the text on your purple images/tabs. It's pretty hard to read the black text since the purple is pretty dark in itself; coupled with the slim font of your tab's/category's text, it's become a wee bit of a strain.
One thing you might find interesting to look into is the @font-face CSS rule---it can provide you with some really nice variety when it comes to the text you display on your pages!
Still, so far so good! I like it! *thumbs up*