Using Chrome in Windows I can't even click through to the examples - I get a blocking pop-up telling me to get Safari. Doesn't that, coupled with the line "soon other modern browsers will take advantage of these same web standards" imply that other browsers are lagging behind so badly they can't even try to run the examples? That seems misleading to me. The standards are not complete, but they are more widely supported than this page seems to suggest.

Contrast with Chrome's Experiments (http://www.chromeexperiments.com/) that you can try on any browser and see how it copes.

Edit: lots of the demos work perfectly well in Chrome if run from here instead: http://developer.apple.com/safaridemos/