Which technologies does this use that are not ubiquitous? Without seeing the examples, I can't think of anything that couldn't be done with canvas + js and would work in practically every browser. Of course that wouldn't be 'pure' CSS but I can't see a reason to insist on that either.
I'm stuck with Firefox 3.6 on this workstation but it does most of HTML5 just fine so being 'unsupported' for some animation is a surprise.
CSS animations like this are proposed in CSS3 but only heavily implemented in Webkit at the moment. Mozilla has some support, IE is entirely and unsurprisingly lacking.
"Publication as a Working Draft does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress." - http://www.w3.org/TR/css3-animations/
Lots of things get promised in IE that don't wind up being very complete, and it'll be quite some time until the IE7/8/9ers fade away.
Right, you can do all of it in JS/Canvas, but hardware acceleration support is lacking. From my understanding, these CSS animations have full hardware acceleration, but like ceejayoz said, only some of the latest browsers have full support at the moment.
I'm stuck with Firefox 3.6 on this workstation but it does most of HTML5 just fine so being 'unsupported' for some animation is a surprise.