I've had a Kindle 3 (wi-fi only version) since before Christmas. I love it!! But I also think it does have some limitations, cookbooks being one of them. Not only do I enjoy the photography of many cookbooks, I would be worried about the potential for disaster by having my kindle in the kitchen while cooking.
For those looking for free e-books, I use Project Gutenberg (sp?). They have thousands of titles, in the public domain, listed for download onto the kindle. From there, I have gotten almost the whole Sherlock Holmes collection, the entire works of Edgar Allen Poe, a number of works of Mark Twain, The Three Musketeers, and numerous others. All downloads from there are free. In fact, it has been insinuated that many of the public domain books that Amazon sells at $0.99 US actually come from Project Gutenberg, where you can get them for free.