The Kindle DRM wasn't hacked to REMOVE the DRM from Kindle purchases, but added to other books so that they too could be read on the Kindle.
Ebook readers have extremely high contrast/readability and are extremely energy-efficient, being able to display several thousand pages of material without needing to recharge. eBooks are a narrow product, but they have their own ways in which PMPs cannot compete.
Hack let you convert encrypted Mobipocket files that were intended for another reader so that that work on Kindle.
The Kindle is already able to read more than just Amazon DRMed content, it can handle a number of 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.