The Kindle is already able to read more than just Amazon DRMed content, it can handle a number of formats.
The Kindle only allows the reading of Amazon DRM-protected content.
Granted the PDF converter seems to have some trouble with graphics PDF's, but for books the converter works very well.
There are converters available from Amazon and/or Mobi for pdf and doc files.
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.