After four years of rolling with a Kindle-branded version of the MOBI file format, Amazon's shifting away from its ebook format in favor of a new Kindle Format 8. The move emphasizes brand new support for HTML5 tags, including embedded fonts, floating page elements, and CSS3 support. Kindle Format 8 will have little effect on plain ol' text ebooks, but more graphic-heavy children's books, graphic novels and technical manuals will have more flexibility when it comes to digital design.
Kindles will still be able to read MOBI files, of course, and Amazon's upcoming platform tools will take care of publishing Format 8 and older files for the growing family of Kindles. That bring us to the catch--only the Kindle Fire, Kindle apps and latest generation hardware will support the HTML5-based format. How convenient, then, that Amazon's now accepting old Kindles in an electronics trade-in program.
The Kindle trade-in results page lists every previous-gen Kindle device, from the 2007 original (still worth $28!) to the Kindle Keyboard and Kindle DX, which is worth the most at $135. Interestingly, Amazon will give a bit more money back for a Special Offers version of the Kindle Keyboard--guess those models are still selling well.
It's a shame the Kindle DX won't get any use out of Kindle Format 8--that larger screen seems perfectly suited for technical manuals and publications looking to get fancy with some CSS stylings.