I don't think creating a new language just to compile the source to Javascript is a good move, especially when Javascript is being under heavily supervised & supported by a huge web development community. If Javascript isn't that expressive or weird, fine, why don't we just fix it or find another replacement? I find myself is comfortable to work on a language that's close to the platform than fancy languages that try to hide/fix trivial problems and take away other good aspects of the language. There are enough languages to learn already and CoffeeScript is probably fade away once these[1] kind[2] of stuffs[3] become stronger.

[1] http://www.ecmascript.org/

[2] http://www.mascaraengine.com/

[3] http://code.google.com/p/traceur-compiler/