The demos have three levels of obstacles for non-Safari browsers even if the other browsers implemented the HTML5 features being demoed (only video and audio; the rest is CSS!) and implemented the proposed CSS features once standardized:
via hsivonen – -webkit-HTML5. Apple promotes open standards by calling them by the wrong name and using the most closed version possible to prevent all other browsers from seeing the effects. Oh and one of the demos doesn’t even work in anything other than the latest version of Mac OSX.