I really like the idea of a flip book layout also. I have been checking a few out but most still use flash.

As far as interactive E-books it makes me think of kids apps for a story book to be used on an I-Pad. Not sure how much I would need this type of feature in the projects I do. I could see this being used by a designer to offer as a product for making a family's book of memories or to make a kids story using their name and story about the family. You see sites offer the picture books for families and kids story books.

Ray