Having bought a nook in April, I've been watching the recent wars rather closely.
First, just before the IPAD was release, Barnes and Noble released a new firmwear version for hte nook, version 1.3 that incorporated a web browser (useless, in my opinion) and also some games (chess and soduku). They also made the page refresh rate a lot faster and smoother and they also increased the speed with which you could "open" your books.
Then, Amazon rolled out a new firmwear as well but pulled it and I don't know if it has been re-instated or not.
Then, the Ipad came out.
Barnes and noble then, just about three or four weeks ago, dropped the price of the Nook with Wifi and 3g by $50 to $199.99 and then also released a WIFI only nook for $149.99 along with a new firmwear, version 1.4 that again made the page refresh rate even faster and added a "go to page" feature that allows you to go to any specific page.
Amazon responded immdiatly with a price cut of their own on the Kindle as well as the Kindle DX. They now offer the Kindly DX in grey which looks really cool.
So, that is where it stands now. Amazon has recently been issued a patent for a folding dual screen e-reader so it will be similar to an actual book with pages on both sides as you hold the device. When that device will be out is anyones best guess.
All in all, I LOVE my nook, more so than the Kindle I played around with. I really like the color touchscreen on the bottom because you can see the actual book covers there. Also, you can just swipe your finger on it to turn the page or use the tactile buttons on both sides of the device to either advance or go back. Other than than, there aren't too many differences. But with the local bookstore having closed just around Christmas, it is really nice to have a device as to where I can shop for books anytime I want and read them right away. Also, another bonus is that if you bring your nook into a Barnes and Noble and show it to the person working at the starbucks counter, YOU GET A FREE COFFEE!! Also, I have always had a book to read since buying the device so buying an ereader has certainly increased my reading, I think I've used it every day since purchasing.
So, that is my nook versus Kindle story. I have seen the Borders e-reader online only and not in person. Not sure the world needs another one but oh well.