There hasn't been a significant upgrade to WPF in years. Microsoft's stance seems to be that "desktop apps" should not be a thing any more - there weren't any WPF sessions at Build, for example.
A reasonable compromise? Advertisers know that most users won't change the default settings, which means that most users will be saying "please track me". How does that align with most user's wishes?
Defaulting tracking to off is only reasonable for advertisers.
To be fair, you'd need two development trees for WinRT anyway - the namespaces are different, for one thing, and the UIs are of course radically different and incompatible.
The Microsoft of 1998 is not the Microsoft of 2012. Today's MS releases a tremendous amount of code under open source licenses - most recently, their entire web development stack (ASP.NET MVC, etc):
I really like the "live" style of these screencasts. It seems almost like I'm pair programming. I appreciate the polished feel of screencasts like the RailsCasts, but this feels more... real somehow.