We recently discussed news that YouTube and Vimeo are each testing their own HTML5 video players using the H.264 format. Firefox does not support H.264, and Mozilla's vice president of engineering, Mike Shaver, has now made a post explaining why. Quoting: "For Mozilla, H.264 is not currently a suitable technology choice. In many countries, it is a patented technology, meaning that it is illegal to use without paying license fees to the MPEG-LA. Without such a license, it is not legal to use or distribute software that produces or consumes H.264-encoded content . Indeed, even distributing H.264 content over the internet or broadcasting it over the airwaves requires the consent of the MPEG-LA, and the current fee exemption for free-to-the-viewer internet delivery is only in effect until the end of 2010. These license fees affect not only browser developers and distributors, but also represent a toll booth on anyone who wishes to produce video content." Mozilla developer Robert O'Callahan has written a blog post on the same subject , following a talk he gave on Friday about the importance of open video on the web.