The hack allow ENCRYPTED Mobi files to be read on the Kindle. So you can buy a DRM-protected mobi book and read it on Kindle.
Non DRM Mobipocket format is already supported on the Kindle - just drag and drop.
Amazon can do a lot of money only from selling kindle, like Apple does with the iPod.
The Kindle has many flaws, but it does allow you to read a few different non-DRM formats.
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.