From the videos, I can see that Twilight Sparkle is an awesome INTx main character pony. I would lean INTP for Twilight but I could see otherwise. And Pinkie Pie does seem very ENFP. Actually I have little objection to most of the typings there. Even with how little I know about Apple Bloom so far, I would describe her as kind of quiet, but expressive, full of ideas and often has a sort of cheeky grin (This is sounding too familiar, lol)
I wish Fluttershy was infp, but there is something in me that agrees that she's isfp. Of course that something is not explaining why I feel she's isfp.
I hate vibes. My vibes rarely give me a great explanation.