Think about waiting somewhere in the middle of the day, or perhaps in an airport while you're traveling, and having immediate access to 100,000 books and hundreds of newspapers and periodicals from this pad in your hand.
Amazon can do a lot of money only from selling kindle, like Apple does with the iPod.
Typically ebook readers are larger than PMP's with larger screens. If you're going to read for a few hours, then the screen of a typical PMP becomes pretty eye-straining (due to size, contrast, and brightness).
Kindles can read a variety of non-proprietary, non-DRM'ed formats. They read TXT, HTML, JPEG, and non-DRM Mobi files directly.
A revolutionary portable reader that wirelessly downloads books, newspapers, magazines and blogs to a crisp, high-resolution electronic paper display that looks and reads like real paper, even in bright sunlight.