Basically, kids love them because the average person who likes Disney is somewhere between 6 and 9. If they're thrown a pop star, be it Hannah Montana or the Jonas Brothers, they'll latch onto it and say, "This is cool!" IT'S NOT!!!
They don't suck, at least not exactly, they have talent, but they are more oriented for the pre-teen - teen audience, once they get older, they'll probably attempt to expand their listenership.