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Wii U

Local co-op isn't dead, and it isn't just for your girlfriend (seriously, if I catch you saying “girlfriend co-op,” things will get heated). Playing games with someone in the same room as you shouldn't be reserved for classic, group-oriented activities. For the last 15 years, Nintendo has tried to breathe new life into playing with friends and family, and the Wii U might have the power to revitalize the concept…if you let it.

Asymmetrical multiplayer is a fancy term for how the Wii U is set up. One player uses the tablet controller while up to four others use more-traditional game pads. Nintendoland, a mini-game oriented project that turns classic Nintendo franchises into theme park attractions, is the first title focusing on asymmetric mechanics. 
In Nintendoland, the person holding the tablet often has some sort of control over the other players. In Animal Crossing Sweet Day, four players are trying to gather sweets while the fifth is a constant aggressor trying to steal what others have collected. Gathering candy becomes a complex game of keep-away and a race to collect the most. This concept only works locally if another display is involved.
Now, Nintendoland is fairly simplistic from what I've seen, but the mechanics are easily re-purposed. Imagine if a Left 4 Dead-style game came out on Wii U, besides that atrociously named ZombiU thing Ubisoft is making. Four friends could play the shooter part while a fifth person actually becomes the director, or the governing intelligence in Left 4 Dead. Rather than shooting zombies, the fifth person gathers points from successful survivor injuries and controls when the horde descends and where special zombies appear. 
I think more people would enjoy seeing beyond the run-and-gun mechanics of any shooter if a separate but still involved display gave them that access. Playing games in the same room then transcends those lingering Goldeneye memories aand turns into a more cerebral struggle against one another. Left 4 Dead is a good example of this because the game's AI is incredibly cruel already, but what if that were actually the person seated to your left that keeps spawning witches in impossible-to-avoid locations? Sure, more people will eventually suffer controller-related injuries, but the concept has a tantalizing complexity. 
Wii U
Girlfriend co-op. I hear this term thrown around quite a lot when it comes to the Wii, and anything with local co-op. Is it simple enough for the eponymous inexperienced person to succeed at? I shouldn't have to explain why stating it is specifically good for girlfriends is heinously sexist, even if your girlfriend isn't very interested in or good at games….
That term unfortunately sums up the view many gamers have of a console with a huge tablet controller rather than cutting edge graphical capabilities. A machine designed to embrace home interaction, and specifically local multiplayer, must exist to satisfy the needs of bored yet inexperienced players and shouldn't interest anyone deeming themselves “hardcore.”
I agree that Nintendo's approach to gaming is much more toy-like than Sony or Microsoft (or was before the motion control craze) but they do know how to make a party experience fun. Nothing says that concept can't evolve into something serious. Televisions are large enough now that splitscreen play is far less annoying.
Of course, the real problem is that no one likes associating with people in the same room anymore, at least not while gaming. Having to go to someone's house conflicts with the pick up and play mentality many multiplayer shooters instill, but I think gamers still need that option. Social interaction is important, and while I've been on the receiving end of several violent Mario Kart sessions, I don't regret sitting in a room with people and playing. 
The idea of asymmetrical multiplayer is intriguing to me because I can see the social aspects of it. I want to sit in the same room with a group of friends I am virtually antagonizing. I want to see their reactions, and eventually take turns so we can all struggle against different kinds of crafty gameplay.
But, seriously, lay off the girlfriend stuff. If social interaction, learning, and having fun are primarily girly concepts, I'm glad I am a girlfriend, and not the person perpetually thinking I can't possibly grasp this whole “video games” thing. Perhaps if games offered the form of social interaction I described above more so-so players might gain an interest in Call of Duty or Halo, rather than chastising you for playing too much.