I played with my friend's iPad 2 today. Thoughts:
What I liked: Waaaaay thinner. Feels much, much lighter as well. The roll-up screen cover is pretty dang cool. Noticeably faster - more "instant". Yay cameras, finally!
What I didn't like: My iPad 1 is already "fast enough" - apps open in seconds, vs. "a" second. Cameras are junk - the front-facing camera looks like a low-res Youtube video, and while the back is HD, it was fairly grainy. The camera on the new iPod Touch beats it by leaps and bounds. I don't know what they were thinking sticking a VGA camera on an XGA screen for video chat, it looks like garbage. Cool that you can video chat on it though - definitely better than doing it on an iTouch or iPhone.
Also, and I didn't think it would bother me, but the screen is the same. I like the screen on my iPad 1 just fine, but keeping the same screen on the iPad 2 just felt
wrong somehow. It's thinner, faster, lighter, but looks the same screen-wise. I dunno. I have no complaints with the original screen, but it did bother me a bit that the second model didn't have a screen upgrade of some kind, considering it's like 95% of the device
Still on the fence about upgrading. I don't really have any reason to, other than just
wanting the new tech, but it doesn't feel like a very compelling upgrade for me right now. I will probably upgrade at some point since our first baby is on the way, so it'd be nice to Facetime with family and not have to be near a computer. If I needed to save weight, I'd snag the new one today, but I carry around a 15-pound laptop, so meh...