#Ember "Ember.js, therefore, is a synthesis of the powerful tools of our native forebears with the lightweight sensibilities of the modern web." "...we're not willing to give you a little bit of rope if we think you'll just end up hanging yourself with it as your app grows. " - Tom Dale
#Backbone "Backbone.js is intended to be fairly agnostic about many common patterns in client-side code." "'Two way data-binding' is avoided. While it certainly makes for a nifty demo, and works for the most basic CRUD, it doesn't tend to be terribly useful in your real-world app." - Jeremy Ashkenas
#Angular "Other frameworks deal with HTML’s shortcomings by either abstracting away HTML, CSS, and/or JavaScript or by providing an imperative way for manipulating the DOM. Neither of these address the root problem that HTML was not designed for dynamic views." "Unlike other frameworks, there is no need to inherit from proprietary types in order to wrap the model in accessors methods. Angular models are plain old JavaScript objects." - angularjs.org