Some friends have bought those. I played with one for a while. As a reader, I think it is pretty cool, and it would also be great for watching movies on a long flight. The display is very nice looking, even HD video on youtube is pretty spectacular. None of the ones I used had 3G, so internet was through WiFi, which is fine for most people. I think 3G is 30 or 40 bucks a month with no contract, which, I think is about what my 3G Blackberry data service costs.
I know a lot of people say it is really expensive compared to a Netbook, but it is very elegant. It's thin, comfortible to use and hold, and the display is awesome. I've realized that while I'm comfortable with techie looking stuff, a lot of people aren't - and this thing is sexy. It's something a hot girl could use, not just a nerd. That counts for a lot.
That said, I don't really see the application for most people over being a toy. I mean, the iPhone I know business people use. But, this thing doesn't fit in your pocket, so unless a guy is carrying a briefcase, or a girl a large purse, it isn't /easy/. And in a business meeting, the applications are one at a time. So if your trying to check e-mail, take notes and browse the web for something people are talking about in your meeting, you can't tab through the applications like you can on a regular Mac.
I heard it can be used as a universal remote, anyone hear about that or how that would work? It would be a pretty freakin' nice universal remote.