Slides from my talk on creating accessible interactive ebooks with EPUB 3 are available:
There are a few videos in the presentation which I’ve pulled out separately:
Using an accessible HTML5-based EPUB with VoiceOver
This demonstrations uses The Restless Universe from The Open University with a screenreader. The publication (somewhere between EPUB 2 and EPUB 3) uses the HTML5 canvas element to present visualizations, and includes alternate versions for the visually-impaired. Though this demo was run on a computer, the EPUB works in iBooks. (Software tools to build these publications available at http://sourceforge.net/projects/bookbind/.)
For each example, I show the visual presentation first, then the alternate screenreader-friendly one.
Creating a screen-readable interactive publication with WAI-ARIA