Going from the Game Boy Advance to the DS, adding a second screen and resistive touch opened up a new world of gameplay possibilities, even if only a minority o

Going from the Game Boy Advance to the DS, adding a second screen and resistive touch opened up a new world of gameplay possibilities, even if only a minority of DS games have really made good use of this configuration. But I can't really see how 3D paves the way for anything gameplay-wise. You can have in-game cues that make use of depth perception, but how much use can that be when you're still only interacting in 2D? I could see something like MotionPlus working here to allow the device itself to be tracked in 3D space, but that gets problematic when the screen is attached to the user's spatial input device. And this is to say nothing of players with limited depth perception.