Of course CoffeeScript code won't run as javascript, it's not a superset. But it operates on the same global scope, the same object model, with similar semantics, so it "is" javascript, unlike other compile-to-js languages.

After reading more about it, I agree that it shouldn't have .js in it's name, or any other language extension, since it's not a framework/library. The fact that the examples are written in CoffeeScript is incidental.