Bill McCoy, IDPF: Epub=XHTML content with navigational structure and metatadats, in a zip-based package. Content paginated on the fly based on screen size, resolution and user font size preferences. Amazon has been accepting Epub for some time and then converting it to their format. The general “on-ramp” to Amazon is Epub.
Goals: expand Epub applicability for global content; improvement for complex, interactive, media-rich titles, increase web standards alignment (HTML5), improve Epub conformance and accessibility. Proposed specification of Epub 3.0 approved today.
Enhancements: video and audio support, audio can be synchronized with text, embedded font support a baseline requirement, improved SVG support, sJavaScript support; core content based on XHTML5; enhanced global language support (vertical writing, writing directions); styling and layout enhancements (multi-col, hyphenation); improved metadata capabilities (including element-level semantics); MathML support; fragment IDs (enables fine-grained x-doc links)
Will supersede SAISY DTBook as the standard delivery format for accessible content. Accessibility-related features in Epub 3: semantic tagging, semantic inflection, audio and video playback synchronized with text display, media overlays, pronunciation lexicon support, MathML support, controls over JavaScript
Beyond Epub 3.): validation programs, education and training, test suites, reading system certification, open source implementations, promoting global adoption, ISO-level standardization, modular development of new Epub capabilities
I see a lot of buzz on twitter and the blogosphere that assume that because Epub 3 supports things like SVG, JavaScript, and MathML, that ebook readers will support them, even if they claim Epub 3 compatibility. The same goes for actual ebooks. For example, a mathematics or physics etextbook might be provided in Epub 3 format and still have its equations embedded as bitmap images, thereby making them inaccessible, uncopyable, and unsearchable. Consumers (and bloggers that influence them) will have to learn to recognize and request these features. This is going to be a controversial and problematic area for years to come. My hope is that organizations will establish quality standards that address this. It would also be nice if quality became more of an area for competition between reader vendors and ebook vendors.
BTW, I think you meant DAISY, not SAISY.