so, i finally bought one, not least because i'm asked every so often about the future of the book, so i should really know more about the subject. verdict... i'd expected the object itself to feel slightly fisher price but i rather liked it, the shape and weight, the way you don't have the hold the page open, the way you can read lying on your side. the qwerty keyboard is horrible but you rarely need it. however... the interface is crap. it's really hard to skip easily back to passages you remember. you can't underline or put a little asterisk at the top of the page. the bookmarking is laborious and practically invisible. even more annoying are the texts themselves, and not just the cheap out-of-copyright ones (the complete works of shakespeare for 67p, for example) which you'd expect to be rubbish, but recently-published books from big, reputable publishers. i was reading (or trying to read) incognito: the secret lives of the brain by david eagleman from canongate. it's a good book, or should be. but it's peppered with typos, some of the illustrations are indecipherable because of the screen size and resolution, and the main text, footnotes and explanatory texts attached to illustrations run confusingly into one another. plus, like all kindle texts (i gather), it consistently turns dashes into hyphens which makes parentheses look like compound words. and when one of these (correctly or incorrectly) compounded words appears at the end of a line, the line is then not justifed, unlike the rest of the paragraph. its looks messy, it's not what the author intended and sometimes it is genuinely confusing. these are all errors which would be considered shoddy, embarrassing and unprofessional in a physical book. astonishingly you can see two of the faults (falsely compounded words and erratic justification) right here in the kindled first page of william boyd's ordinary thurnderstorms which amazon chose to use in its full page press advert.
on the other hand, my 7 year-old son, who is a reluctant reader, really likes it, so it can't be wholly evil.