@ drsteve: You also can't highlight or annotate on a Kindle, even a Kindle DX, which is what I really need the tablet to be able to do.

I don't think that anyone doing serious academic reading could be happy with the limitations of 6" Kindle or other small, basic eReader. Again, it's a niche capability (many avid readers, particularly those who read for pleasure, don't need to annotate), but one that is indispensable to many in academia. 11