Something I've noticed is that "kids these days" are surprisingly conversant with music predating sometimes even their parents' birth. YouTube means you can check out pretty much any band you hear about from any time period without being held hostage by the selection of your local record store and/or forking over $12.95+ for something you don't know if you're going to like. And so any kid now who expresses an interest in metal to his friends will get sent directly to Black Sabbath's "Paranoid", and will probably be wearing an Ozzy shirt about 2 weeks later.