To join the many other responses to this episode, here are my own thoughts on the premiere.

I am deeply impressed with the maturity and seriousness of the issues with which the premiere dealt, and by how adeptly they managed to handle them while simultaneously keeping the episode enjoyable and accessible to a wide audience. It's a morality story in the finest sense and the way they managed to pull it all together reminds me of the best of Star Trek, e.g., a show which excelled at this. Much of what we see in this episode reminds me of the themes Karl Popper addressed in The Open Society and its Enemies, so much so that I think this episode is an articulate defense, in the context of this fictional universe, of many of the ideals of the open society understood in the broadest sense: the ability to explore who we are coupled with the growth and maturation that can come only by the critical interaction of our own views and perspectives with those of the people around us, by which we open ourselves out of a self-defeating inwardness that stunts our ability to flourish. We need other people, other views, differences, to be fully ourselves and that is one of the most astounding things about life--it's precisely the core message, I think, of the friendship of the mane six and of this show. And the mane six defend that very view by showing the hollowness and ultimate inhumanity (in...ponyanity?) of the closed society and tribalistic approach we see Starlight putting forward. Not only can it only be enforced with the most appalling methods (we see plenty of those in this episode), but it leaves the ponies subject to it caricatures of what a flourishing person ought to be (I think we can safely say the ponies are persons, though of course nonhuman persons) and can be (as evidenced by the mane six themselves). The temptation to the sort of views that Starlight panders is for some strong, because it is hard to make the open society function--it's hard to make friendship work, to put it directly in the context of the show--and it always is imperfect, but it is worth fighting for and worth the effort. This episode does a wonderful job reminding us of these things. I think it's an always timely lesson and one that is thematically completely in touch with the best morals of this show.