I wonder what will happen since Miley is 18 now. I'm sure the tween population will find the next Hanna Montana (whatever they might call it). Can't quite pull a "kid" show when you are 20+ years old. So what does a star do when her face is no longer wanted on lunch boxes, notepads, video games, etc etc etc. She could go into acting, but I remember some critic said that she really need some coaching to act anything but "Hanna"
So career wise, she might have peaked depending the road she is taking.