The PS3 already has this, its called sixaxis... and its rarely used, thats because its more accessible to look using the R3 stick than moving the controller. and i think because of the circualr shape of the R3 stick there is a lot more control and accuracy over how you move around and look.
besides, would hardcore gamers want to pay £130 so they can move the controller to look and move rather than use the anolgue stick??