The idea, really, is books as API...books free of their paper and static eBook containers.
Imagine being able to subscribe to a book about Ruby on Rails that you can read anywhere on any device (online or not), annotate, share and discuss via social media, and is media rich (includes videos, color images, even apps). Now imagine that when the author updates even one word you (the reader) get that update immediately. Imagine being able to write parts of the book via the Crowd. Imagine, as an author or publisher, being able to get detailed analytics about any word, paragraph, page, or chapter of a book. Imagine a chapter being part of several books at the same time. Imagine being able to re-sort a book's chapter not based on author order but on reader-indicated usefulness or popularity.
This is what we're shooting for. The possibilities for books are endless when they become data in its purest form.
We don't have a working demo. We do have a slide-show of the concept, here:
I also give a tour to a journalist in this video: