The iPad appears to have been a lightbulb moment for the forum, whose working group, after much criticism, now wants to add these and other features to take ePub from version 2.0.1 to 2.1.

Apple’s tablet, and its iBooks app, supports the format - but a wave of publishers is now looking beyond ePub and toward snazzier standards. Penguin Books’ CEO said last month: “We will be embedding audio, video and streaming in to everything we do. The ePub format, which is the standard for e-books at the present, is designed to support traditional narrative text, but not this cool stuff that we’re now talking about. So for the time being at least we’ll be creating a lot of our content as applications, for sale on app stores ... rather than in e-books.”

A critical shift may be happening, as content publishers consider leaving open formats for the lockdown of proprietary standards that let them do more, in executable code. HTML is “clunky”, “a central problem” and “never really succeeded in the way that we had hoped”, according to Wired design director Scott Dadich. Two decades of magazines’ web presentation could soon count as merely a “design experiment”.

ePub’s fightback is so far modest - the working group concedes “not all conceivable enhancements can be accomplished in this release” and “reinventing the wheel is explicitly discouraged”. It’s not even tasked with standardising DRM, which is under another group’s remit.

It’s suggesting piggybacking the HTML5 revision, which itself includes video, and supporting a new, XML-based metadata structure. But the group won’t report its recommendations to the International Digital Publishing Forum until May 2011.