Update (Dec 27, 2012).The graph does not reflect the correct stats of Google's dart language.
Earlier this year, Microsoft
announced a new JavaScript extension language called
TypeScript.
TypeScript is a new script language developed by Microsoft for application-scale JavaScript development. TypeScript extends JavaScript and compiles to plain JavaScript. Since it is JavaScript, it eventually can run in any browser, host or OS. It is an open source language.
It may be too early to say but so far, Google Trends showing no or very little progress compare to JavaScript and Google's similar language DART.