I would go with a subway tile in one of the colors in the granite. A glass tile would work as well, especially since the pattern in the granite is so subdued as to almost be like a solid. I would just focus on making sure my color matches were good.

A good way to start figuring out what will work is to look at tile on thetileshop.com, and order samples so you can see how they look against the granite.

I like the idea of a glass subway tile or a light mosiac tile with some sheen to it. Check out my "Backsplash!" Ideabook for some of the ones I have saved. We are also in the process of picking out a backsplash for our home & having a difficult time making a decision. I posted a very similar request for suggestions today!