We purchased a Kindle about a month ago, I haven't had a chance to use it yet, DW won't put it down. The Kindle steers you toward Amazon for book purchases, but DW figured out how to download books from other sites.
We were going to buy a Sony E-reader at Fry's, but the salesman said that the Kindle would be a better buy; really appreciated his honesty. We got it at Target, since Fry's doesn't sell Kindles.
It can download some games also, but that's something we don't really care about.