I know I'm late to the party but I own a Nook Color and a Kindle 3 and I must say I'm enjoying the Kindle 3 a lot more, its just a nice little gadget.and I'm not sure if its been mentioned but there is a program called http://calibre-ebook.com/ which is a book organizer, format converter and allows you to transfer your books to your e-reader in seconds. I'd be lost without this program since I've acquired over 3,000 e-books these past few years.
Sorry, still nothing like going to the bookstore and getting a good hard copy !