If we assume Ember, Backbone + friends, and Angular are already 'big', then React is definitely the one on the come up. For all intents and purposes those 4 ar

If we assume Ember, Backbone + friends, and Angular are already 'big', then React is definitely the one on the come up. For all intents and purposes those 4 are really the only ones being talked about IMO. Polymer is thrown about too but from what I understand it's not exactly production ready (could be mistaken)