I'm not even bothering reading the Google Groups discussion, but please! I thought Mozilla had "blacklisted" H264 on the desktop because it was not universal and because it was harmful to have a closed codec dominate the web!
And now they are going to support it on Android? What the hell Mozilla? The mobile web is already lousy with its lack of variety and bigger and bigger restraining to closed components, and you want to take it further?!?!? Get WebM on the mobile! Make use of the freaking hardware chip, but don't make things worse!
Sorry, but I had to rant. I am all for using the system codecs on the browser (less work, the people get more video support if the browser bundles the codec installer), but I don't think supporting H264 on such a crippled web will do any good.