Yes, and I think it is more popular than ever with the Bibbity Bobbity (sp?) Boutique open.
I have seen CM's refer to the little girls as princesses, and I am sure they get lots of guests saying "how cute!" (which I have done!)
I have seen a few little girls in full costume including very uncomfortable "glass" slipper sandals.It made me cringe as I saw them hobble along. Most girls have tennies on, but I thought it would be cute to decorate sneakers with rhinestones, glitter, and ribbon laces to wear with a princess dress.