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According to Sony, the recently released PSP Slim, a redesign of the original PSP, has sold 1 million units in Japan two months after its release. To give perspective to these sales figures, the PlayStation 3 took 8 months to sell 1 million units, although it had a much larger price tag.
The PSP Slim achieved its 1 million sold milestone nearly two weeks faster than the original PSP did when it was released in Japan, which is admirable considering that the PSP redesign is still an older system.