I’m sitting in the back of a Dynamic Languages session by John Lam and Jim Hugunin called “Just Glue it! Ruby and the DLR in Silverlight”. John Lam was a recent hire (January) to Microsoft. Prior to this he was working the Ruby CLR. Jim Hugunin is an architect on the CLR focused on DLR (Dynamic Language Runtime). He joined Microsoft specifically to work on Iron Python and make sure that the CLR was one of the best platform for dynamic languages such as Python.
They are showing a ton of very cool stuff. They are doing all of their programming in TextMate on a Mac. The samples so far have been in JavaScript, Ruby, Python and even Dynamic VB.
I recommend that you check out this session on the http://www.visitmix.com site when the recording gets up there. They do a fantastic job showing the power and ease of dev as well as poking a lot of fun at each other.
What’s a lot of fun is the interplay between all of the different languages. For example, they created a library in C# that they could pull in and leverage from Ruby and a JavaScript lib that was doing some 3D work that they pulled in and did some quick and easy work.