The WebM project has made a preview release of a VP8 decoder component for Windows Media Foundation. With this bit of software installed one can view VP8 videos in Internet Explorer straight with the HTML5 video tag. WebM can already play in the latest release versions of Google Chrome, Opera and in the Firefox 4 RC.
Earlier Microsoft has clarified that while the only format supported by the browser out-of-the-box would be H.264, however third parties could release a decoder component that would enabe VP8 playback in the HTML5 tag. Recent version of Windows include an H.264 decoder with the OS.
For those unaware of what WebM is, it is a media format that has been released as an open specification by Google, with the intent to provide the web with a royalty free, high quality, open codec that can be used for delivering video.
While the HTML5 specification is still devoid of an official codec for video, it should be clear that H.264 is not that codec. For a truly free and open web there needs to be a standard royalty free and open format. While H.264 is arguably a better codec (in terms of quality) than VP8 / WebM, the latter is definitely a more sensible choice for a web where no one should need to get a licence to be a full member of the ecosystem.
This does not seem as clear to Microsoft as their announcement of the same WebM playback component still seems rather hostile to the format.
Just a while back Google unveiled a royalty-free hardware encoder IP that would could potentially allow future smartphones (and other devices) to record full HD content in the VP8 format.
If you've installed Internet Explorer 9, and the WebM component, you can check out Microsoft's demo page to see it in action. Itching to play more WebM videos? Currently the biggest and most popular source of WebM videos would have to be YouTube, which offers them as an option for those who are part of the YouTube HTML5 beta program.
WebM is the future of open video on the web, it is a high-quality codec, that is significantly better than its alternative open alternative Theora. It isn't better than H.264, however its quality is good enough to be a feasible format for delivering web media.