This looks fantastic, especially with the integration with HTML5BP. Awesome work!

Just wondering if you considered using RequireJS instead of namespacing? Backbone plays quite nicely with RequireJS if you use James Burke's version which has been forked to be compatible: https://github.com/jrburke/backbone/blob/optamd/backbone.js

More info here: http://jcreamerlive.com/2011/12/09/backbonejs-modular-app-us...