I'm not sure this will happen. The only users who are unable to watch WebM are iPhone/iPad/Safari users. You can use WebM in IE9 (when you install the codec).

I'm not sure this will happen. The only users who are unable to watch WebM are iPhone/iPad/Safari users. You can use WebM in IE9 (when you install the codec). So as a webdeveloper the path of the least resistance for me will be WebM. You'll get support in Chrome, Firefox, Opera and IE9.