The reason is, don't get confident in magic. Learn good OOJS, then learn what some simple helpers can do. At that point, you'll understand the magic of angular and ember better. Maybe others won't agree, but, as an anagoly, you really shouldn't jump into android development before you have a good handle on java.
I've heard Ember is better for "data/model-driven" apps whereas Angular is better for "interaction-driven" ones. Is this an appropriate analogy? I wish I had the time to explore both for their own merits.
If you were going to develop the next Gmail, which would you choose and why?
Ember + Rails is a potent combo because the two frameworks are built off of the same underlying principles.
Is Data really as fudged up as everyone seems to believe? Do you see EPF having the potential to take its place?