"What is EPUB 3?" Article from O'Reilly
October 6, 2011
O'Reilly Media, in collaboration with the IDPF, have just released a free (registration required) white paper "What is EPUB 3?", authored by EPUB 3 spec editor Matt Garrish. Per the catalog description: "This article walks you through the format and puts it in its place in the digital landscape, explaining why EPUB 3 is set to become the new global standard for ebooks as it also becomes the new accessible standard for ebooks".