Luigi's Mansion 2 may be coming to the Wii U and the 3DS, according to a UK retailer. The upcoming sequel was unveiled for the 3DS and shown at E3 last year. Despite this, Play.com currently has two pre-order listings for the game: One for the 3DS version of the game, and one for the Wii U.
Luigi's Mansion 2 was not on the rumored list of Wii U launch titles leaked earlier this month. That list proved fruitful (kind of) when Ubisoft announced that their upcoming game Avengers: Battle for Earth would be released on the Wii U this fall.
With E3 and full disclosure on the Wii U launch on the horizon, we're hyper-sensitive to any and all possibilities. That said, it's important to remember that retailer listing aren't necessarily evidence of the game's existence. The double listing could be a mistake on the part of the retailer or a placeholder entered into the system just in case.