Personally I love the idea of authors earning more for their efforts, I think that's great, but there are so many unintended (by consumers, anyway) costs of Amazon using its reach for this kind of thing -- publishers get squeezed, so they produce fewer books, bookstores get squeezed, so more of them close up shop, commerce flows ever more directly to Amazon, choice gets limited... I just don't like it.  I buy a ton of stuff from Amazon, but I'm starting to think maybe that's such a great thing anymore, in the long run.