I agree the Civ5 demo didn't look good, but did you watch all the way through to the Papers, Please demo? I think using both pads to control the mouse cursor could end up being really good. In fact, it could be even better than a real mouse in some ways, since you sometimes have to lift a real mouse but you shouldn't ever have to lift both thumbs at once.
> I think using both pads to control the mouse cursor could end up being really good.
I don't know. I've tried using two hands on a big trackpad once and it just gets confusing. Maybe with more practice but I felt like it was more a brain confused problem than a material one.
Certainly there would be a learning curve, but in a well-designed game learning the input device is part of the fun. I think there's nothing about controlling a mouse pointer with both thumbs that would make it inherently less learnable than e.g. traditional gamepad FPS controls (which are anything but intuitive).