I hope mozilla can now afford H.264 licenses. They are the last holdout to make web video easy.
Chrome: http://blog.chromium.org/2011/01/html-video-codec-support-in...
Opera: See an opinion piece at http://my.opera.com/haavard/blog/2011/01/13/openness
In other words, Mozilla would need to be able to buy the entire H.264 patent pool. Even at $300M/year, they're nowhere near that.