GameFly just listed Animal Crossing: New Leaf as a Wii U title, available here with a release date of TBD. Whether this means Nintendo is actually planning a cross-platform release for the village simulation remains to be seen, but it wouldn’t be too far-fetched. When Animal Crossing: City Folk released on the Wii, people who played Animal Crossing: Wild World on their Nintendo DS could transfer their save files from the DS to the Wii to continue their town on the Wii version of the game.
Animal Crossing: New Leaf has been available in Japan as a 3DS title for several months with no release date in sight for North America or Europe. It’s been speculated that the 3DS game would release in Q2 2013, but that might be delayed if Nintendo is also working a Wii U version of the game for all three regions. Satoru Iwata was recently surprised at how well New Leaf was doing in Japan, so it could be that New Leaf could be a system seller for some people.