re: Apple's iBooks Author Software: Just Say No
There are several things not being understood here. First is that the largest publisher and seller of e-books is Amazon. Amazon's format is completely propriatary. Understand that. Yet, it doesn't stop publishers from publishing using other formats for other sellers like Apple and Barnes & Noble.
In addition, we have various app stores, each using their own formats and development tools.
In this case, Apple's program is called iBook Author. It's clearly labeled. The purpose is to publish books to sell in Apple's iBook Store. But Apple does allow the material to be published elsewhere if given away for free. That's more than Amazon allows.
If other software is used, then authors can publish their books through that, and sell them. Right now, they won't be as good that way, but it can be done. After all all the material for these books is produced outside of Apple's program. It's just put together there, and uses the features to allow special functions.
Adobe has their program for something similar, and it's also propriatary. But Adobe has no way to publish or sell those books.