Has the writer of the article used the Wii U? Or read anything about it? The device described in that patent is no more related to the Wii U than any handheld device with a camera on the rear; Wii U, 3DS, DSi, iphone, ipad, pretty much any other smartphone or tablet, and even a lot of non smart phones.
Look at the picture. This technology requires you to point the small screen at a section of the tv screen, and it shows you the part of the tv screen that you are pointing at, and then overlays stuff on top. i.e. it lets you use the second screen to find hidden objects, such as the ghost in the picture. They did not patent the use of a screen on your controller, that would be too general to count as a patent. What they did patent was a very specific form of gameplay along the lines of AR games like invisimals.