It is true that the dining room rotates. It takes somewhere between 45 and 60 minutes to make a complete revolutions.
I don't think it is at all overrated. Our family has eaten there on every trip; it's the only place we can say that about. The price went up quite a bit last year, but I think it's as much worth it as any TS restaurant. That's just for the food, not even including the characters.