Nintendo has filed a most interesting patent for a Wii Remote. The patent application suggests a snap-on device that attaches to the top of the controller that provides a flat panel of LEDs that will light up when touched.
When touched, a mirror bounces these lights into the infra-sensor in the remote, which apparently converts this into positional data if we understand what we are looking at. The concept seems to be very valuable to the Wii U, as the unit only allows a single player to use its single touch screen controller at a time.
This could be a solution to address this issue, as Nintendo has said that the Wii remotes are compatible with the Wii U. Only time will tell, but we are not sure that an innovation like this would be necessary or help to drive the development of titles for it on the older Wii console.