posted an interesting chart today showing his company's ebook downloads broken down by format over the past two and a half years. Clearly, the dominance of Adobe's PDF is thinning under pressure from EPUB and MOBI.
As a Droid owner, I find it interesting that Android as an OS is on fire but Android as an ebook format is pretty lackluster. Perhaps this is because Android has yet to make its initial splash in the tablet space. EPUB, in contrast, is the native choice for Apple devices as well as Sony's Reader, the Barnes & Noble Nook, and the Kobo eReader. Kindle uses Amazon's proprietary AZW format, which is based on MOBI. Interesting that in the last few weeks you can see MOBI eating into EPUB share. Looks like Santa Clause may be heading down Amazon's lane.