The IDPF has posted a good overview document to 3.0 that is worth spending a little time with. But here is a brief summary of some of the proposed new ‘features’, or changes, in EPUB 3.0:
- Metadata: ability to include more metadata directly in the file(s), or link to external metadata resources.
- Display (Rendering and CSS): more HTML5 thoughout, some CSS3.
- Global Language Support: including right-to-left and vertical based character sets.
- …and more…
I also recommend checking out Liza Daly’s presentation from TOC Frankfurt.