As a downloader... I just can't take the time to care, really. I don't have a device that reads KF8 or ePub, but 9 times out of ten, I'm going to download the highest quality format and whip it into the shape I want for my Kindle anyway. That means more than likely, I'd start with the KF8 or ePub format. Whether the KF8 version comes with the fallback mobi version included, doesn't really matter to me in the least.
As an uploader... I'm always going to provide an optimized combo version in case the reader doesn't have the skills (or desire) to diddle with the formatting. Those it does matter to, can always strip out the mobi portion if it bugs them.
Last edited by DiapDealer; 05-31-2012 at 02:09 PM.