If you read some of the Kindle discussion groups, you'll see people complaining about "no backlighting", and then a few days/weeks later they will be lauding the fact that it has no backlighting.
Kindles can read a variety of non-proprietary, non-DRM'ed formats. They read TXT, HTML, JPEG, and non-DRM Mobi files directly.
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.
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).
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