I'm a reader. In addition to the audio books, I am always reading at least one printed book. A friend got a Kindle last year, and I just had to have one, too.
My Kindle has started more conversations with strangers than any other item I've ever carried. Somebody seems to ask me about it whenever I use it in public. That might be considered a bad thing by some people, but I've always enjoyed giving a little demo.
I have dozens of books on the Kindle. I have two versions of the Bible and a giant dictionary (plus the Kindle comes with a dictionary built-in). I can buy books in a few seconds; for instance, two weeks ago, my son told me about Getting Things Done by David Allen, and after I hung up the phone, I purchased the book. Another time, I heard an interview with the author of Scratch Beginnings, and bought that on the spot. Two great reads, by the way.
One can load dozens of reference volumes onto the Kindle, as long as you've got it in a supported format. For instance, Word files, text files, .pdf files, and Mobi files (unless they've got DRM) can be used on the Kindle. Searching every book on the Kindle is nifty - and a great way to navigate your portable research library.
To buy a book, I make sure the Kindle's wireless is on. Then I click on the menu button and choose, Shop In Kindle Store. I run a search for the desired book, look at a page about the book, even cruise the customer reviews if I want. The price of the book displays. I click to buy the book, Amazon charges my credit card :), and in just a few seconds, the book is on the Kindle.
I get many of my books free, though. Although the Kindle came with a user's guide (handily loaded on the Kindle), I also purchased The Kindle Cookbook and learned a lot more ways to get my money's worth out of this gizmo. In addition, I subscribed to an online group, Kindle Corner, and often get good ideas from them, including lots of free books on Amazon.
Kindle keeps tracks of where I was in each book. I'm currently in about four books, in different spots. When I open that book again, it goes to the spot.
The Kindle does have a slightly gimpy internet browser, and I've used it a number of times. In particular, I used it for several hours once while stuck at an airport. It's okay if you're going to websites which are mainly text. My husband was using our laptop, and I had a better signal on the Kindle's "Whispernet" than he had from the airport wireless service.
The Kindle's wireless service is free.
I have also played with news feeds on the Kindle, and that works okay. I haven't subscribed to magazines on the Kindle (yet).
One of the issues that we book-lovers struggle with is storing lots and lots of books. I do not want my house any more filled with books than it is now, yet I find it pretty painful to get rid of books. Kindle books don't take up space and you can keep them. However, a real downside is that you can't share them easily.
I've read a great many customer reviews and comments about the Kindle. Many of them mention the gray scale screen. One person compared it to an Etch A Sketch. That's about right for the original Kindle screen. It uses "electronic ink" and I understand that the Kindle 2 has a lot more shades of gray and was designed to be better at displaying pictures. Because the Kindle is not backlit like a computer, and because it has a font size button that lets me use a bigger font, it is much easier on my eyes than reading either a paper book or a computer screen. I am somewhat farsighted, and I am also looking at a computer or paper all day - in other words, using my eyes all day, and then going home with tired eyes. Reading the Kindle in the evening is quite comfortable.
The Kindle 1 is rightly critized for not being good at displaying pictures. Most pictures are just too small. They worked on this with the second version.
The second version will also read the book in a mechanical voice. It is also only 1/4" thick, which would give me more space in my purse...
One very interesting development is Amazon's incursion into the textbook business with Kindle editions. I imagine the Kindle DX, which is touted for reading newspapers (it's BIG), will be terrific for textbooks, assuming Amazon can get a big enough piece of that market to make a difference.
Our college student son probably spends $500 or more each semester on textbooks. They're expensive in part because of their relatively small printing runs and distribution, and the Kindle might be a good solution for those two same reasons. There's no printing, and distribution is electronic.