One thing I forgot to mention is a know a guy who was around Tom Petty when he was really young in Gainesville, and was playing with other people on the scene. He said, and this is pretty much verbatim:

"Whenever Tom Petty walked into a room, everything stopped. He just had this look and this aura about him that said 'you guys have just been clowning around but I'm about to show you how it's done.' And you could also distinctly hear him saying, without speaking a word, 'Oh, and by the way I plan on completely dominating the entire rock and roll planet even though no one knows me yet. But I will be one of the most famous people you have ever heard of.' And so he did, and so he was."

The guy said he acted that way from the time he was a teenager and hardly knew how to play.

I just thought that was funny.