If you're eligible for the iPhone 5 upgrade the decision is really black or white. As in literally getting the black one or the white one. There are great Talmudic debates over which one, exactly, is superior and why, but in reality they both look quite good. The white seems clean and neat, while the black seems dark, sleek, and cool.
Personally, I went with the black model (I liked that the sides are anodized black, plus the black goes better with my Retina MacBook Pro and black iPad). But what about you?