Google (with support from Mozilla, Opera, and others) announced today that they'll be freely—as in beer & as in speech—licensing their VP8 video compression technology, as part of developing "a high-quality, open video format for the web that is freely available to everyone." Seems like excellent news insofar as this royalty-free format will continue to lower entry barriers to making and distributing web video.
There are two other main browser makers: Microsoft and Apple. Apple has not yet formally responded to Google's VP8/WebM announcement, but it's likely that their eventual response will be a complicated one, considering that Apple has structured much of its video ecosystem around the competing (and relatively proprietary) H.264 format, but also currently features a YouTube application on a number of its mobile devices.
Microsoft, on the other hand, appears to be both tacitly embracing and hedging against WebM. The Internet Explorer project manager writes that "when it comes to HTML5, we’re all in." But Microsoft also notes that "some web groups have cited concerns about patent issues with similar codecs and the costs that may be associated with shipping codecs not covered by patent licenses." And even if a successful patent lawsuit against WebM is less likely than one against Ogg, Microsoft seems unwilling, at least for now, to give the same default & native support to WebM/VP8 that it gives to H264. Thus "IE9 will support playback of H.264 video as well as VP8 video when the user has installed a VP8 codec on Windows." In other words, the burden is on the user, not the browser maker, to install the WebM codec. Easy for users to do on desktops, perhaps (if the user has install privileges), but not so easy on mobile devices!
In general, this Ars Technica article (+ comments) spins out numerous different ways in which these patent questions might play out. Perhaps the lack of initial straightforward support from other browser makers shouldn't be surprising, since most companies aren't exactly willing to do awesome things first and hope the patent/copyright questions will eventually fall into place. But it will certainly be interesting to see what alliances are ultimately struck; whether the adoption of a free and open video standard will significantly shift the landscape of web video; and whether in the future we'll have more, or fewer, points of transaction/control between video makers and users.