If you look for introductory material, try the Open Model CourseWare (OMCW) Home page.
Well, the basic idea is a very old one and it is one of the basic principles behind formal languages.
This method has been used for decades in computer science, for example the compiler generators in the late 60ies and early 70ies.
But the recent developments are very promising, because the techniques and methods seem mature enough
to change the way we think about software development.