As far as I'm concern, the iPhone as with most of Apples products owe their success to mass marketing and Hollywood. There is nothing special about the iPhone, it is totally locked down, I don't know about you but I don't want to be treated like a child.
We live in a culture of followers, OOHHH MYY GOOODDD, what the new trend. Have you seen the phone whats her name has on the Hills, I just have to have it.
Thats what the iPhone owes it success to.