MVC in JS (Sencha, Backbone, Ember)

We will try to learn about different ways to implement Model View Controller mechanism in JS. How can we structure our applications to take advantage of the MVC paradigm.
We will also look outside Sencha and Backbone and if time permits into Ember.js to see how these MVC frameworks could be used in conjuction with Sencha (if at all) and what the similarities and differences are.
Joe will lead the discussion.