Make sure to check in on Yelp to get a buy one/get one credit.
The Biltmore store is a ton of fun with its goofy red floor and its looping cartoons. And you may even run into a pro athlete (Suns' forward Grant Hill, who opened the door for my niece, who about died when I told her who he was).
Mojo is not cheap, but the service and atmosphere are superb and I'd say the price point for the total experience is about right. Kids and adults appreciate the sample cups and the ingredient bar is always well stocked.
For lactose hating guts, Mojo offers a dairy-free yogurt, which I'd never put in my mouth but seems like a very nice gesture toward the afflicted.