Overall it looks pretty good. The very top header with the logo is too plain ... also seen many logos with the blocks, work on something new. The font size in the nav look a little big, maybe make them a little smaller. The side links are nice, gives a soft feel to the site.
I must say the thing i myself am not happy with is the header, the nav bar i just went for it big and simple.. as i wanted and needed it to be as easy to navigate as possible. Glad you like it though.. I think I will have another stab at a better header.
I like it a lot. The layout, colors and text looks great, don't change anything except the header(I agree with the others), design a better one to blend with the layout and you have a great looking site.