I actually saw an iPad "in the wild" for the first time on Monday. I asked the woman who was using it how she liked it, and she was raving about it. She said she uses it now for reading instead of her Kindle. I didn't ask her to hold it, but the thing that struck me was how large it looked. (That's compared to my Kindle 3 or my Kindle 1.) I also noticed that the screen had a little bit of a bluish cast, but that might've been the viewing angle or the brightness level she had it at.
The conclusion I came away with was the same that I reached for the Kindle DX: It's too large for me. Because of my chair, it'd be difficult to carry around comfortably, or in my backpack. I'll admit that there was a bit of a wow factor in seeing one, though.