Apple’s iBooks textbooks for iPad stakes a position against openness in e-book publishing.
A post on Glazblog (the author says he’s “Co-chairman of the W3C CSS Working Group”; it would be nice if he gave his name) gives technical details. It uses XML namespaces that aren’t publicly documented, a nonstandard MIME type, and a private CSS extension.
This means you can’t view the books on anything but iOS. If Apple ever drops support for the format, it’s obsolete and impossible to support.
On top of this, the EULA for iBooks Author restricts sale of books created with it to the Apple Store. You can give away your books by any channel you like, but if you sell them, you must use the Apple Store. This means that if Apple doesn’t accept your book for publication, you can’t sell it in that format. (Except maybe in France, as Glazblog amusingly notes.) This is like having a compiler that lets you create software which you may sell only through Petitmol, or a video application that forbids you from selling your movies through anyone but FooTube. I can’t think of a precedent for this.
Authors normally would like to be able to take a book to a different publisher if their previous one loses interest. With books created with iBooks Author, you can’t do that, for both technical and legal reasons. The format isn’t under DRM, though, and the exclusivity applies to the format, not the content. As far as I can tell, you should be able to extract most of the content and republish it in a different format.
Apple’s restrictions make iBooks textbooks unsuitable for assignment to classes, unless the school is willing to give every student an iPad. Those who use other devices would be left out in the cold.
Apart from the restrictions, does Apple’s new format offer anything exciting? My own reaction, from briefly looking at a few sample books on a co-worker’s iPad, is that the interactive graphics are attention-getting, but the most important form of “interactivity” with a textbook is trying things out on your own — playing with the equations, writing sentences in the language, whatever. The best accessory for that is still a pencil and paper.