From your slide-show, it seems you don't "pay" authors at all. You take a percentage of their royalties, apparently for inserting adverts in other people's books? I find it very unlikely that readers will accept books with advertising and tracking, and even more unlikely that they'll switch from their existing eReader in order to be advertised to. EPUB3 seems benefit neither the author nor the reader, only the marketer.
http://www.slideshare.net/ezgraves/ho...