I think that it may be simpler to learn than both angular and ember.

Unfortunately, given the fact that it's missing 2 way data binding and it's not declarative, you end up with lots of boilerplate code and in the end you invest more time in writing your backbone application than in learning angular and writing the application in it.

To be honest, I'd only start a new project in angular or ember because they are extremely productive frameworks. Backbone was great more than 2 years ago.

I politely disagree with ending up with more boilerplate code with marionette... you're ending up with _less_ boilerplate code when using marionette with backbone, and even when including marionette, your "boilerplate" code is necessary configuration... binding dom elements, events, template handling, rendering, data serialization... even more so if you're doing it in CoffeeScript.

behold... a view in 3 lines of code.

  class Views.AlbumTracks extends Marionette.CompositeView
    className: 'album-tracks'
    template: 'album-tracks'

In angular you'd never need the line with className, so you'd end up with even less code, because of its declarative style.

A good reading when thinking that's necessary to bind dom elements, events, etc is here: http://stackoverflow.com/questions/14994391/how-do-i-think-i...