* Made the return values of Collection's set, add, remove, and reset more useful. Instead of returning this, they now return the changed (added, removed or updated) model or list of models.
Given that calling `collection.add(foo)` returned `collection`, when were you ever using the return value for anything? Going forward you might, but I would be very surprised if much if any code was broken by this.
* Backbone Views no longer automatically attach options passed to the constructor as this.options, but you can do it yourself if you prefer.
This might require going through your code base, but it's just adding one line in the `initialize` function:
initialize: function(options) {
this.options = options;
Annoying if you have hundreds of views that directly extend Backbone.View, but not something that should take a day to fix?Am I missing something?