This episode was very, very awesome. Like a whole bunch of people out there, I'd wondered about Twilight and what the writers were up to with the element of harmony crown thingy and the crazy good magical powers. Got the answer, and I'm pretty happy.
It would have been wonderful if they'd had more time through the season to build drama, lots and lots of drama leading up to the change, but hey it worked. Worked so well! I can't wait until next season and see how Twilight adjusts. She seems like a creature of habit and it'd be fun watching her work princess-hood into her schedule and friendships.