Blogger Nate Hoffelder has claimed that Amazon's replacement to the Mobi 7 ebook format, the HTML5-powered Kindle Format 8 (KF8), may already be used in Kindle Fire-exclusive graphic novels and magazines. The blogger cites an unnamed source, and says that a beta version of the new format is being tested by a select group of publishers. Apparently he's got a copy of the beta and some supporting guidelines, and after working with the software to convert an ePub to KF8, he said he's a "little surprised how well they transferred over." Unfortunately, it sounds like KF8 won't be getting the full HTML5 experience: in addition to using proprietary tags, KF8 won't support Javascript or some HTML5 tags like canvas, which will limit interactivity — but it's a start.