In my application I'm adding [Ember.js](http://emberjs.com/) objects to my the data hash.  Ember objects have observer functions tied to data properties that will get fired when a property is modified.  The merge operation copies the data but in doing so unsets the observers.  

In my case I don't want to have a clone of the object in this hash, I want the object itself so that the object state remains consistent within the application.  I hadn't intended for this change to be a part of the pull request, but why does the object need to be cloned in the first place?