Here's the current state of HTML5 video: Microsoft and Apple are betting on H.264, while Firefox, Chrome, and Opera are rooting for WebM. Google was actually in favor of both H.264 and WebM up until earlier this month, when the search giant decided to drop H.264 support completely, even though the former is widely used and the latter is not. The company also announced that it would release WebM plugins for Internet Explorer 9 and Safari. Although IE9 supports H.264, excluding all other codecs, Microsoft is making an exception for WebM, as long as the user installs the corresponding codec, and is helping Google ensure the plug-in works properly."
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