The iBooks 2.0 textbook format

So slots appear to be like text frames that the content flows through?

That would be a useful extension if it got more widespread usage.

The thought that occurs to me though is whether this will appear in webkit at some stage or if it is just for the closed source iBooks side of things.

The list posting at W3C suggests that at least some of it may appear in the public webkit at some stage.

I guess the dream of a fully EPUB 3 standards compliant authoring tool was too good to be true. The devil is in the CSS.