Just wanted to say thanks to the Mozilla folks for having the guts to put Ogg in the browser. I know it won't have a deep impact overnight, but I think it might have deep long-term impacts.
Project idea for the willing and able: Make the video tag work cross browser. Swap via JS to Flash (or Silverlight or Quicktime or Java or ...) if video's not supported, automatically picking a different source. And make the paired sources easier to prepare on the server.
I guess the down side is that no one distributes video themselves, due to the large size, but maybe such a project would encourage the Vimeos, Hulus, and YouTubes of the world to consider support for open video. The goal in this case would be to make it easy for them to swap to Ogg (or whatever) video when Flash is unavailable.
Bonus points to Firefox if they ever get Canvas 3D in there. Even better to have an additional integrated mode for content inside and out of a 3D scene graph. (I suppose shouldn't get my hopes too high for Bullet physics ...)