Actually, over the past few months I kept running into several people who'd have the perfect scenario for an EPUB3 and multimedia book. I agree that "traditional" books will be as valid, but they can come in both EPUB2 or EPUB3, it shouldn't make a difference. Adding multimedia to the eBook is optional anyway, so it'll depend on what people want to pack into their books, and how.
On the Mac, I can use Murasaki just fine with the EPUB3 as well. (To test what I have. Doesn't mean it's complete :-))
Having said that: still no answer to the question. I think I'll noodle around this weekend, see how if I can find something that works.
EDIT: Well, the "position:fixed;" doesn't seem to work.
Last edited by _savage; 01-25-2013 at 08:55 AM.