But its not an Obj-C to javascript compiler: its Objective-J, a entirely new language that is a strict superset of Javascript: pure Javascript is also valid Obj-J. You wouldnt call Objective-C an "Objective C to C compiler" since valid C is Objective-C.

Contrast this with GWT, which is a Java to Javascript compiler. Unless you wrap it in a native method, you dont write javascript with GWT: i.e. GWT is a Java-Javascript compiler, not a new language like Obj-J