Compiling MSIL to JS

Google is using GWT (Google Web Toolkit), that is compiling Java to JavaScript.
Some prominent people in Microsoft have been developing similar system for .NET, and apparently that is now abandoned.
Instead, a new language TypeScript is developed
(by other prominent Microsoft people :)

From the Archives: Erik Meijer and Mark Shields - Compiling MSIL to JS | Charles | Channel 9:
"today it lives here I believe https://github.com/Reactive-Extensions/IL2JS
...
This was open-sourced. Mark and Erik no longer work at MS and so this project is no longer alive inside MS."

Success of projects, in particular in Microsoft, is tricky...
It at least as much "sales and marketing" skills as the technical excellence...