Apple has overtaken Wal-Mart to become the biggest music retailer in the US, outselling the big CD retailers for the first time.
Sales at iTunes over January and February also surpassed Best Buy and Amazon, which took third and fourth places respectively.
"We launched iTunes less than five years ago, and it has now become the number one music retailer in the world," said Eddy Cue, vice president of iTunes at Apple.
"We are thrilled, and would like to thank all our customers for helping us reach this incredible milestone."
Apple quoted sales figures from market research firm NPD Group, which counts one CD as representing 12 tracks, confirming the company's status as number one music retailer.
Hot on the heels of Apple's milestone, MySpace yesterday announced a joint venture with Sony BMG, Warner Music and Universal to offer a music download service that will go head-to-head with iTunes.
The company described MySpace Music as a "360-degree global solution" that would "evolve users ability to discover, share and socialise by adding commerce and music management tools".
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