I'm not sure if some of the features I would prefer will ever find itself into the epub format; such as full justification for starters. I'm rather persnickety
about the layout of my books. Epub and the whole ragged right makes reading that much less enjoyable for me. Also, font embedding is pretty crucial for me as well. I'm not sure if that is just a limitation on the software I'm using or if the Epub standard already supports it? Perhaps I will reexamine using Epub when those issues are addressed.