The Kindle only allows the reading of Amazon DRM-protected content.
As glued to the net as we all are, there's vast quantities of content that is not available online.
Non DRM Mobipocket format is already supported on the Kindle - just drag and drop.
We've known for some time already that Amazon's AZW files are actually Mobi files, but Amazon didn't share Kindle's Mobi PID which would allow one to buy encrypted Mobi books for Kindle.
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.