Sony (NYSE: SNE) and KDDI have announced they will let digital music be shared between Sony’s portable and home-use music players and mobile handsets from KDDI starting in December. The service will arrive through free software upgrades. “The deal is an attempt by Sony and KDDI to get the jump on rivals like Apple (NSDQ: AAPL) Inc., which has dominated the field so far with its combination of iPod portable music players and iTunes download software, in the next round of the battle for the digital download market” states MarketWatch—although Japan is different from the global market in that 94 percent of digital downloads occur on the mobile. For Sony it’s a good move, since it encourages KDDIs subscribers (the second largest carrier in Japan) to buy Sony products for their house—and it closed down its digital music store. For KDDI it’s good too, of course, since giving customers more options to play their music will probably result in them buying more music.

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