You make this sound like its a bad thing, but that's open-source always and forever. Scratch your own itch.
http://gwtgallery.appspot.com/
http://www.gwtsite.com/whos-using-gwt/
http://www.reddit.com/r/programming/comments/aqsxq/does_anyo...
http://www.quora.com/What-web-applications-use-Google-Web-To...
Many new Google services these days use GWT, like Google Flights, Hotels, the new YouTube editor, Google Offers, etc. AdWords is written in GWT too and is quite large (millions of lines)
One of the problems Dart hopes to solve is to have a large codebase(apps easily into the millions of lines of code) that is toolable, and statically optimizable. Javascript is particularly poor at this.
The Closure Compiler was actually invented by the Google Mail and Calendar teams as a way to wrangle Javascript and tame it's suckier bits to enable sane development of large apps.