Is C3 the Secret Sauce for Windows 8 Programming?

This MSR paper describes an HTML/CSS/JS platform that seems to tie in with Microsoft's recent conspicuously-not-mentioning-.NET talk of Windows 8. This paper is still in a conference proceedings, so it wouldn't seem on the verge of productization, but there are so many questions raised by Microsoft's recent endorsement of JS + HTML for desktop applications that it bears investigation.