They're roughly the same size, shape, and price. They use the same technology for displaying text. But there are some important differences
(To read a full comparison of the Nook and the Kindle, read Rich Jaroslovsky's review.)
The Good: Includes an additional color screen, permits friends to borrow downloaded books from one another, and allows free browsing of entire books when the user is in a Barnes & Noble store.
The Bad: Slow to boot up, format text, and display it on the screen. Color screen and Wi-Fi connection drain battery life.
The Good: Lighter and faster than the Nook, it boasts longer battery life, and each of its features has been thoroughly tested in the market.
The Bad: The physical keyboard seems clunky and unnecessary. And it lacks some clever features, such as lending rights.