I've been using AngularJS for a few months on a side project of mine and it greatly helped move a lot of the code complexity to the client side. Hooking it up with a REST API was simple and got rid of almost all of the server side rendering.

Here's a particularly useful sample app, implemented in both Angular as well as Backbone.

http://coenraets.org/blog/2012/02/sample-application-with-an...