I agree with everything but your last point: > Apple should have just completely created their own format instead of extending ePub, and we wouldn't be having

I agree with everything but your last point: > Apple should have just completely created their own format instead of extending ePub, and we wouldn't be having this discussion. Now Apple has become the convenient scapegoat for ePub's failure, whilst others, most notably Amazon, get a free pass for doing exactly the same. That seems like a terrible reason to head off on your own and create a totally new format. Case in point, look at audio/video CODECs. Under the hood, many of them have startling similarities. The consumer has no idea they're similar, because they're named differently. More directly, what is wrong with extending ePub, provided you don't represent it as ePub. Gruber's best points are made on a technical basis, not a business basis. Apple isn't calling the iBooks Author output ePub. That would be egregious. As is typical in the technology space, everyone is conflating arguments. They're pissed about Apple's business tactics, and so the argument spreads like fire in a field of dry grass. From a black box perspective, iBooks files are proprietary. Whether their "based on" ePub is no more relevant than the fact that VP8 bears similarities to H.264 and many other video CODECs [1]. 1 - http://x264dev.multimedia.cx/archives/377 http://x264dev.multimedia.cx/archives/377