New Sunglasses for Running?

I've debating whether I should get some new sunglasses exclusively for running and possibly cycling. Lately I've been using my Spy polarized sunglasses that I've had for the longest time. They've done the job well but they aren't the lightest for active sports. I think it's time to have a devoted pair of sunglasses for running and cycling.

Last month I was able to try a few Nike and Under Armour sunglasses at Road Runner Sports. The Nike sunglasses definitely stood out. They were extremely light and felt as though I wasn't wearing sunglasses as all. They have a great nose pad that provides great grip so the sunglasses won't fall off. But I've been also looking at Oakley's as well. The half jackets and the Flak jackets look very sporty. I hope to try them on this weekend and possibly make a decision.