Firefox 4 sneak peek flaunts Google open video codec
Be like Opera
Mozilla has turned out a Firefox 4 prototype that includes Google's newly open sourced  WebM video format, while Opera has rolled the format into a developer build of its own.
Last month, Google open sourced  the VP8 video codec that it nabbed as part of its $124.6 million acquisition of video compression outfit On2 Technologies, and this was paired with the open source Ogg Vorbis audio codec to create a larger royalty-free media format known as WebM. Apple and Microsoft continue to put their weight behind the royalty-encumbered H.264 video codec, but Mozilla and Opera have sided with Google, vowing to use the WebM in tandem with the fledgling HTML5 video tag. Both outfits were on hand at Google's annual developer conference when WebM was announced.
On Monday, Mozilla released  a fifth developer preview based on its Gecko 1.9.3 rendering engine, which will eventually morph into Firefox 4, due for official launch in November . A beta should arrive later this month. The latest developer preview — detailed here  — adds not only WebM but also hardware acceleration on Windows and Mac for HTML5 videos viewed in full-screen mode.
You can download the preview for Mac, Windows, or Linux, and for the first time, 64-bit builds are available for Mac and Linux — though these do not include support for 32-bit plugins and are considered "highly experimental."
Meanwhile, Opera has added  WebM to its latest developer snapshot. When Google announced WebM, Opera showed off a demo build that uses the new format, and this was released to the web. But this marks the debut of the format in an official developer preview.
Available for Windows, Mac, and FreeBSD/Linux, the preview also adds support for a handful of other open standards, including HTML5 offline web applications, geolocation (though this is only partially available on FreeBSD/Linux), and web workers, for running background tasks. You'll also notice that Microsoft Bing is now the default search engine on the speed-dial page — though Google is still the default for the main search box.
The latest developer build of Google Chrome also includes WebM , but we aren't likely to see such support from Apple or Microsoft anytime soon. Both are part of the MPEG-LA patent pool that licenses H.264. Steve Jobs has indicated  he has no interest in WebM, and though Microsoft has said it won't object to IE9 surfers using WebM, they'll have to install it on their own. IE9 will ship with H.264. ®