First let me say that I share custody of my iPad with my wife so it doesn't travel everywhere with me although that is becoming more of a difficult decision as I use it more. Still not sure I can rationalize spending more of my money on a second one in one household.
As far as a consumption device, I think I would trade in my computer today. The battery life is amazing actually and the graphics and videos are simply "sick" as a student explained when seeing it. If all I needed to do was surf the web, check email, run my calendar, watch videos, blog and listen to music, it would be my only device. However, the things that I have to do for the rest of my job, it is not designed to do which is totally understandable I guess.
Now as far as a classroom tool, I think it will begin the development of a very good 1:1 solution that will become available in 2 years whether it is from Apple or another company. These ease of use, size, weight and clarity are all there. I could see them being a great solution for @christianlong's TedxProject since it is centered around watching Ted videos (amazing on the iPad), researching information from the Internet (very slick and fast on the iPad) and blogging (doing now easily on the iPad). However, it still does not have the capability of operating a lot of the web 2.0 tools yet (or maybe it does and I just haven't figured out how to do it). For example, I cannot edit a google doc although I can view it. I cannot figure out how to edit a wiki even though it seems like it wants to let me. If you could even just solve those two issues, I may push to get them in the hands of my students. Then I would use the computer labs for the video editing and other more substantial tools that students need to be utilizing.
I'm still more fascinated in how this device will change how we teach. I'm convinced it will change the publishing industry and thus how the majority of people distributed their writing to the world. It will make multimedia and hyperlink writing even more important and in my opinion push the 'tipping point'.
Well those are one man's opinion of the iPad in education to toss into the sea of those much more intelligent than I so take it for what it's worth.