Uh huh.
Digging through the MSDN documentation sometimes reveal that some under-used properties in CSS3 can be used as of IE9. :O Like vh, vw, vm/vmin, etc... these units are rarely used, but now I can have the height and width of something to be set to be exactly the viewport, but slightly smaller, without having to rely on nonstandard behaviour. I think WebKit also had just gotten around to implementing it in a dev build.