If you were wondering why Apple chose HTML5 over Flash for the iPhone and iPad, you can see for yourself now. The company posted several examples of the types of content that can be made using the technology. Included in the showcase are video, audio, picture galleries and more. It’s definitely worth a look.
Apple posts HTML 5 demo page [CNET]
But for a so-called "standards" demo don't you find it odd that it only runs in Safari?
Not really, since it's a new "standard" and Firefox and Chrome haven't adopted it fully yet.
Not odd at all. This is new stuff and first impressions count a lot–especially with this timing around WWDC. Why risk this golden opportunity by letting it run on other browsers. That'd be reckless, if not foolish.
No harm in promoting one's own browser, anyway.