This may be true, but still Ember forces you to use uses get() and set() while in angular you can just use plain old javascript objects. Basically Angular does dirty checking to keep track of changes while Ember knows of your changes because you are using get() and set()(1).
In my opinion this sucks. I love being able to use plain old javascript objects in Angular. Not having to extend every object with ember.observable is a big win for me. When O.o lands Angular will be just as fast (if not faster) as Ember but without the need to instantiate new Ember objects, and always use get() and set() on them.
Of course Ember could change its API in the future, but Angular won't need an API change because its already using plain old javascript objects.