I just got done reading a transcript of a speech Richard M. Stallman did back in 2002 about Lisp and Emacs. I've clipped a quote that's included below about his motivations to create Guile. One of my thoughts are: Why wasn't this done for the web? Lisp lists as markup, Lisp to script, and nirvana with a Lisp. The quote is also along the lines of what MS wants to do with their common language runtime.
There's an interesting benefit you can get from using such a powerful language as a version of Lisp as your primary extensibility language. You can implement other languages by translating them into your primary language. If your primary language is TCL, you can't very easily implement Lisp by translating it into TCL. But if your primary language is Lisp, it's not that hard to implement other things by translating them. Our idea was that if each extensible application supported Scheme, you could write an implementation of TCL or Python or Perl in Scheme that translates that program into Scheme. Then you could load that into any application and customize it in your favorite language and it would work with other customizations as well. (RMS's "My Lisp Experiences and the Development of GNU Emacs")
