I spent a good bit of time this morning taking a peek under the hood at iBooks Author and the files it builds. By request, here is a quick summary of some of the information I gathered on the topic. I warn you that this is going to be a non-generalist post, so do feel free to skip ahead on the site if this kind of info isn't really your thing.
The iBooks format appears to be an EPUB-like variant specific to Apple. Like EPUB, it's a zipped up file that contains an archive of the materials that make up the book. Inside, you find an Open Packaging folder and a META-INF Open Container Format folder, with its container.xml file. Unlike EPUB with its application/xhtml+xml mimetype, .ibooks uses application/x-ibooks+zip.
There are
