While it's nice that Ember.js provides a run loop that's not enough, just batching all your updates into one place just puts all of the work together, you'll still going to pay for the work and in the worse case you have to hand coalesce, yuck. In Om if there is no work ... there is no work, it's implicit in the system! No need for hand coalescing your state changes.

Angular.js still suffers as shown by the optimization article I linked to in my post. These kinds of typical optimizations can and should be pushed out of the user's hands.