[Hopka]

From the rather vague text I can imagine they are doing matrix multiplication in JavaScript and assigning the end result to a CSS transform. Instead of doing multiple transforms in CSS which is slower. The end result is smoother HTML5 animations but I haven't yet figured out where they reinvented the web.

[e12e]

It's been a while since I looked at transition (and 3d transition) support from css -- but this sounds really counter intuitive -- shouldn't the browsers be able to make these changes themselves, in c++/c/hand-tuned machine code at that?

http://www.w3.org/TR/css3-transforms/#transform-property

"A transformation is applied to the coordinate system an element renders in through the ‘transform’ property. This property contains a list of transform functions. The final transformation value for a coordinate system is obtained by converting each function in the list to its corresponding matrix like defined in Mathematical Description of Transform Functions, then multiplying the matrices."

On a side note: this looks like something that should work (transformation/transition) with javascript disabled -- we've (rather) recently gotten drop-down menus that don't require javascript -- seems like a bit of a step backwards to require javascript for (some uses) of basic transformations if that's being used as part of the essential ux for a page...