Our position on vendor prefixed css properties

I was looking through the site and found a few css properties that are
vendor-prefixed, like
http://docs.webplatform.org/wiki/css/properties/-ms-radial-gradient.

Are we adding are this vendor prefixed pages or removing them? I would go
for the latter. Especially in this case because, as far as I know, there
was never a stable IE version that had this property.

Paul.