At the end of August, the band Arcade Fire launched an online experiment with Google that allowed fans to build a personalized music video to accompany the new song "We Used to Wait." But the video was more than a normal video: it was a collection of video windows within the Web browser that provided, among other images, aerial and street-level footage of any address a user provided (via Google Maps).
This sort of functionality would be impossible to offer using most online video players–pieces of software that run via a separate browser plug-in–like Adobe’s Flash and Microsoft’s Silverlight. But the Arcade Fire video ran directly from the browser and was built with the emerging Web programming language HTML5.
Although the World Wide Web Consortium (W3C), which governs new Web standards, has yet to sign off on all of the possible features of HTML5 video, a number of websites are charging ahead with the technology. CNN and The Onion, for instance, have used it to build out their video libraries, in part because it offers new design options. "The technology is far more expressive," says Ben Galbraith, director of developer relations at mobile computing company Palm. "It frees up graphic designers and potentially unlocks developers."
The fact that Apple’s iPhone, iPod, and iPad products don’t run Flash-based videos is also pressuring media companies to look to HTML5 as a way to reach as large an audience as possible.
Source[ Technology Review]