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Over the past few years, we have watched Apple climb the music sales chart courtesy of the iTunes. Last month we learned that Apple passed Best Buy to become the number two retailer in the the US in December. Now, Apple has ascended to the top of the charts, surpassing Wal-Mart for the first time ever, according to an NPD MusicWatch Survey for the month January contained in an internal Apple e-mail which was leaked to Ars Technica but has not been officially published.

The news was announced in an e-mail sent this afternoon to some Apple employees, a copy of which was seen by Ars Technica. It includes a screenshot of an Excel file showing the top ten music retailers in the US for January 2008, and Apple is at the top of the list. The iTunes Store leads the pack with 19 percent, Wal-Mart (which includes the brick-and-mortar stores as well as its online properties) is second with 15 percent, and Best Buy is third with 13 percent. Amazon is a distant fourth at 6 percent, trailed by the likes of Borders, Circuit City, and Barnes & Noble. Rhapsody is in the tenth slot with 1 percent.

The fact that a digital-only retailer has ascended to the top of the sales charts is not unexpected, but it does demonstrate just how much the music landscape has changed since the beginning of the decade.

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