
The UK retailers Play.com has listed Luigi's Mansion 2 for the Wii U. It couldn't be an error since the 3DS version is also listed. Nintendo revealed the tittle for the first time on the E3 2011 and since Nintendo has been really quiet about it. Would like to see Luigi's Mansion 2 on the WiiU? We'll just have to way till E3 2012 which is in just a few weeks.
Source
Play.com