It doesn't matter that Monster Hunter 3 Ultimate isn't out for the Wii U yet. Capcom is planning ahead and has confirmed that a software update will be released a month after the game's March 19th Wii U launch.
The April software update will add online cross-region functionality, allowing North American and European gamers to play together online in up to four-player battles. The update will also allow off-TV play, meaning you to play the game using just the Wii U GamePad without the need for a TV screen. Capcom's willingness to listen to community feedback and incorporate the requested features is a great sign for fans of the series. It's an even more impressive feat that they are planning this so far in advance — the wait will only be a month.
Monster Hunter 3 Ultimate will continue to be supported with free download quests for "several months" after its release. The first quest will be available at launch on March 19, 2013. The game will be available for Wii U and 3DS.