Better late than never I guess. It has taken 11 versions, but Microsoft is finally starting to catch-up and adopt established web standard protocols and features. The fact they implemented silent auto-updating a while ago hopefully helps with the uptake.
No, it won't be available for windows xp or vista or 7. However every other browser will be. I will still be coding towards IE8 for the next like 2-3 years till everyone leaves windows xp, which is currently the most popular version of IE, which means really simple css which makes life ridiculously easy like nth-child and last-child won't be available to me.
