I don't yet even have my iPad (I'm waiting until after next month to see how much I'll be dropping on the 4G iPhone) but I already know I'll be going for a Vaja
http://www.vajacases.com/. Yeah, they are expensive, but they are without a doubt the highest quality leather cases I've ever seen. I have a thing for leather, what can I say. I've had a Vaja on my iPhone 3G since it came out, and the thing still looks brand new.
Now having said that... I also have my eye on the stuff from HardGraft
http://shop.hardgraft.com/, another favorite of mine. Why do I have to love things that cost sooo much money?