Simply loading an mpeg or mov file works. I set content type to video/mpeg and encode in H.264. It works fine.

The HTML5 video tag is not supported, if I go to http://webkit.org/blog/140/html5-media-support/ I get the "This is fallback content..." message at the bottom of the post. The current official desktop Safari build handles the video tag, so perhaps it is coming.

I think a may have thought of a way to make it work...will post it on HN when I am done if this thread does not produce any good answers