Let's not forget the television audience.
If I am in bed on Sunday mornings channel surfing, I will always stop when I see Olsteen.
He preaches a positive outlook. One Sunday, I may actually attend his church in person.
I enjoy listening to him. We need a positive message because Christians have often been pounded into the ground by people who judge and condemn and expect them to act a certain way. We've often been expected to be worms and not worthy (and this is from other Christians!). It can get to you sometimes.