There are nicer languages out there than either one, but I always feel drawn back to the main language for the platform. But that's also part of why I'd rather see good JS tools than use GWT. I just haven't seen them yet. Still, JS is the metal in browsers.
I'd also be curious to see a server-side JS framework get traction. Hasn't happened yet despite many attempts. Nothing is yet (and perhaps never will be) "the metal" on the server.