Let's do some math!
Sales of Digital Music Triple - Yahoo! News: "Apple Computer Inc.'s iTunes online music store accounts for 82 percent of legal downloads in the United States. The company has sold more than 500 million songs online and about 22 million iPod digital music players."
Now let's see. That works out to be some 610,000,000 songs legally downloaded since someone actually started counting. And I have about 700 of those (plus a few hundred ripped from legally purchased CDs). That is about 1/10th of 1 percent or about one millionth of the total number of songs legally downloaded (1.1475409836065573770491803278689e-4 for the true mathophile). Wow. And to think it all fits on an iPod. A 'mini' no less (pun intended).
If you are wondering why it seems "everyone" is buying an iPod, try to fit 1/10th percent of 610,000,000 songs on any other machine and have it fit into a shirt pocket. I love my blue iPod mini. Goodness knows my eyes would appreciate the ultrasharp and bright color screen of the Nano, there's nothing like the solid feel of the aluminum case of a mini.