Of course it will appear on Wii U.
http://www.videogamer.com/xbox360/battlefield_4/news/battlefield_4_headed_to_wii_u_report.html
http://www.gamefaqs.com/boards/631516-wii-u/65116550
http://www.pcgameshardware.de/Battlefield-3-PC-221396/News/Battlefield-3-doch-nicht-fuer-Wii-U-Battlefield-4-soll-kommen-1016793/