I just got one and I'm going to Uni on Sunday to do Interactive Multimedia Design, I'm also a web designer and a freelance web designer. My points:-
If your thinking of using the Macbook only for design etc, there is no point as the resolution is no good for it. I cannot work any of the adobe suite on it. Thankfully I have a 22in monitor which is linked to it, so it saves me that problem.
Speed wise it is great. I got the middle spec with 2GB of ram and it opens all the adobe suite in about 15 seconds (first start) if you close them and open them again its about half that, plus I just leave them all open at the same time and there is no slow downs.
You cannot play games on it. Hopeless.
It gets dirty easily (i've had it since monday and i can already see it turning into a darker shade of white even though I'm trying not to let it get that way. I would go for the black model even though its a waste of 100£.
It looks cool.
If you want portability and your on a budget I would go for it. If you have more funds I would got for one of the Macbook Pro's because of the larger resolution, or even an iMac (if you don't need portability but are on a budget).