Forbes.com: When IPod Sales Run Out Of Steam

Forbes.com: When IPod Sales Run Out Of Steam: "Yes, indeed, Apple's (nasdaq: AAPL - news - people ) little music box has done a heck of a job in boosting the company's fortunes. There are some 10 million iPods in use around the world, and if the figures in my spreadsheet are correct, it has contributed $2.8 billion in gross revenue over the ten quarters since the company started breaking out iPod sales in its results. More than 42% of that revenue came during the quarter that just ended.
To hear the media tell it, everyone has an iPod, and if they don't already have one, they're soon going to get one. But the fact is not everyone does. Not even by a long shot.
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I don't mean to sound bearish about Apple or about the iPod. But as good as Apple's latest results were, I've started to wonder how long the iPod miracle can last. Nothing this good can last forever."

Timely reality check on overall market potential and dynamics.