As you probably know, a Google I/O conference was held today and a lot of blogs said they will announce big things. And big it was: Google officially announced the release of an open source, royalty-free video format called WebM which will be using the VP8 codec Google aquired from On2 as well as Vorbis audio.
The WebM launch is supported by Mozilla, Opera, Google and more than forty other publishers, software and hardware vendors.
For now, WebM is not part of the HTML5 specifications but support for it will be added by Chrome, Firefox and Opera, as a part of the <video> tag (update: Internet Explorer 9 will also be supporting VP8). Most probably today's snapshots of Chrome(ium), Opera and Firefox already include this. You can already download patched FFmpeg or DirectShow for Windows (Gstreamer support coming soon) from HERE. There is also a patch for MPlayer.
WebM is already part of the YouTube HTML5 experimental feature - all the 720p or higher videos uploaded to YouTube starting today will be encoded using WebM (but also in H.264). However Google claims (according to Mozilla) to transcode all YouTube existing videos into WebM sometime soon.
How will Adobe handle this? Well, Engadget points out that Adobe is rolling VP8 support into Flash Player, but hopefully websites such as YouTube will start using the HTML5 <video> tag instead of Adobe Flash by default.
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