The whole ePub is the prevailing format in the USA argument is incorrect. Although it is true that more reader devices and eBookstores use ePub than any other format in the USA, far fewer eBooks are sold with ePub formatting than with mobi formatting. All the major USA book publishers claim that 67% of all the eBooks they sell are sold through Amazon. That translates to 2 out of every 3 eBooks being sold with Amazon formatting (mobi). If Amazon wants to change their format to whatever, it is clear that they will set the standard that others can follow are not. They are the BIG dog on the block and whatever format they use will become the leading standard, like it or not. I'm just thankful they are starting to move away from mobi, and even if it isn't ePub it looks like a much better format than mobi.