There’s a nice little introduction to CSS3 selectors on XML.com which contains this little comment:

The Mozilla Project has already implemented several CSS3 selectors and is working on implementing the rest soon. The other vendors aren’t far behind, either.

Where those “other vendors” doesn’t actually include the market leader with over 90% of the share, obviously.

What do you reckon? 2010? Ever? After all, if you’ve got Longhorn you’ve got rich internet controls provided by your OS far surpassing anything you can do in CSS or Javascript. Why would they ever need to improve their current rendering engine?