Kindle's e-Book DRM Is Broken
Amazon sells content for the Kindle in a proprietary format, .azw. It contains DRM to prevent users from transferring copyrighted content to other devices. Think of it as the e-book version of what Apple's FairPlay DRM used to represent.
The hack lets users convert the Kindle's e-books into PDF files, allowing them to be read on any number of non-Amazon e-book readers as well as computers, naturally. The hacker, known only as Labba, posed a challenge on a hacker forum and with a little help broke the DRM.
One can expect Amazon.com will come up with a change to halt the hacking, but Labba said that he feels that when Amazon.com does release a "fix," he will be able to hack it again. Consider it jailbreaking the Kindle: new software, new hack, just as with the iPhone.