If you ever get the chance pick up one of creative's or archo's early mp3 players and take a look at what the interface was like
I had a black Mp3 player from China about 2 or 3 months before the first ipod. It was USB, and I loaded songs onto it from my PC.
It basically looked like a small ipod; the display wasn't quite as nice, and it was smaller, however it looked almost identical, had a wheel and everything.
They took a product, improved it slightly, and then marketed the shit out of it. itunes happened because of the ipod, not the other way round.
Cg