I couldn't say anything was wrong with the design -- colors, layout, navigation all work for me.

If I had to be picky... I might say to attempt to reduce the size of the header graphic or initial portfolio graphic if you could... so that when people view the portfolio material (site designs, etc.) they DO NOT HAVE TO SCROLL DOWN (given you appear to be showing one at a time anyway) to make sure they're seeing everything.

I'm running a monitor at 1280 x 1028 basically and when viewing the portfolio you feel as though you might just be missing the bottom bit -- so you scroll.

NO -- this is not a show stopper but it would be nice to eliminate the scroll factor.

Now you may be sitting on a nice higher resolution screen so it may not be affecting you at all. Really well done though in my opinion and you wouldn't have to change anything unless you wanted to.