According to Phil Harrison, the reason why “Sony didn’t incorporate rumble into SIXAXIS wasn’t related to a lawsuit over patent rights, but because it was a ‘last generation feature’.
I believe that the Sixaxis controller offers game designers and developers far more opportunity for future innovation than rumble ever did. Now, rumble I think was the last generation feature; it’s not the next-generation feature. I think motion sensitivity is. And we don’t see the need to do that. Having said that, there will be specific game function controllers, potentially like steering wheels that do include vibration or feedback function — not from us but from third parties