John Noring explains the requirements demanded of an eBook standard and how the existing Open EBook Publication Structure meets those demands. Also, he makes a case for proprietary standards not fitting the bill.
It's a pretty long article (disclosure: I haven't finished it), but well documented and explained.
Given what I now know of PDF, QuickTime, Flash, SMIL, et. al. if OEBPS is the real deal it would also make a nice format for news publishers.