"We are looking carefully at the DS, and certainly aren’t ruling out developing for it in the future. However, for right now, our focus is on Rock Band Unplugged as a PSP title." - Greg LoPiccolo, VP of product development at Harmonix

To be honest, I'm quite surprised that the franchise hasn't already hit the DS. Guitar Hero has seen quite a successful launch on the platform, and I'm sure Rock Band could do the same.

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