Don't have any experience with the Kindle, but love, love, love, wanna marry my nook. Have never read so much in my entire life. B&N has scads of free and reasonably priced content. The Nook is supposed to be able to download other content, library and other sources, but I've never tried it. B&N offers a free Nookbook each Friday. Sometimes I want them and sometimes I don't. Have the Nook ap on my phone and really like reading on my phone. A lot of my friends don't get that, but it's small yet the print is the same size as any book. Ya just have to drag a finger across the screen to "turn the page" more often. My nook isn't backlit, so it's easy to read outside in the sun. My phone is backlit so I can sit in a dark room with my husband and read while he watches sports. Everybody's together and happy. Only problem, and this would be the same for both Kindle and Nook, is that when I'm on a plane, I can't read from the time they make us turn off our electronic devises until about 10 minutes after take off when they say it's ok to use them again. That's the only fault, I've encountered.
Love, love, love this technology.