Tough question. I DO prefer the GMC over the Chevy version this year. The current Dodge looks good, and I've liked the current Ford F150. All very close I think. And it depends on color! I don't like the Nissan at all, and I only like the Tundra over the Chevy but not over the GMC/Dodge/Ford. And now there's an updated '09 Ford F150 to look at.
So to answer your question, the one that looks best to me is:
NONE! It all depends on the day and the color
I can't choose.
Now if your asking about which one I'd buy, that's a WHOLE 'nuther story. I never buy a vehicle on looks.