I was thinking about getting one of these for reading books and digital comics. Do they even have colored screens? I know nothing about these things.
All the kindle style stuff are black and white, color might be a while.
I-Pad is pretty sweet, look up the videos. I'm not an apple person but that is the one product I would consider if I did not have to pay for it.
Otherwise expect some sick tablets within the next few months running Ubuntu and Windows 7. That will allow you to go with any software you want and have better access to your computing power (as opposed to blocked multi tasking or needing a million aps because the OS does not do anything).
Also:
http://dvice.com/archives/2010/04/screw-e-books-g.php