Cool, that means it'll appear in ebook reading systems in five to ten years.
It'll be in PDF sooner, and my experience is that PDF >> any other system for ebooks. I liked the idea of EPUB but when I recently installed an EPUB reader to read some files I was shocked at how awful it looked whereas for 15 years I've been reading PDF files on tablets with relish.
Are you speaking just about technical books?
Because I can’t imagine anyone trying to read a novel in epub vs pdf on a phone or epub reader and going with the latter.