I am not sure why people have a problem with the console's library at this point, yes it does need more games so people can have more choice, but 2 of the biggest releases, Mario Kart and Smash, will be here before we know it. I can understand having a problem with the launch library or the period up until maybe this past holiday season but its getting more games now. It should then have enough games to warrant a purchase. Can you really not wait until May, I know I can wait, I have plenty of other games to play in the meantime. Do people buy these games, play them and then put them down, immediately expecting another game to come out? I don't know but just between the 3DS and the Wii U I have more than enough to play and that doesn't even include backwards compatibility. And I am unemployed.. so theoretically I should have infinite time for video games but I still have tons of other things I have to do. If I counted every game in the DS/3DS/Wii and Wii U game libraries that I would like to play I probably wouldn't even have enough time in my life ever to play them all not including upcoming releases.
If people are buying a game, beating it in one day and then putting it down then expecting another to be right there waiting for them, there is just a problem with consumer culture in general and I don't think anyone can do a thing about it. A game like Mario Kart, Smash, Zelda or Pokemon should be savored, and not beaten in one night and put down. Also there are online modes, so there should be more than enough entertainment with those 2 games even for someone with a lot of time on their hands. If there is online play you theoretically can never be bored with a game, as long as other people are online playing and they don't take down the servers. Those 2 games provided they both come out in may should last fans at least through Jan and February without getting bored. I am still playing through Pokemon, a game I bought on release last October, though I already played all the way through Y version and am about halfway through X. It is now March, and I am still not done with the experience yet, and I likely won't be for another few months. I haven't even finished White and White 2 yet, so I have hundreds of hours of playing to do between those 2 titles alone. I did finish black and black 2 though.
In Wii Fit U I haven't even discovered half of the activities yet, there are so many. This game definitely fixes the problem with the original Wii Fit, as that one was extremely limited in what you could do, I can see people getting bored of a title like that. This one is worth the money people, especially if you have a balance board lying around.
If you buy a game then immediately expect another big game to come out, be prepared to be disappointed by the Wii U and life in general..
Despite this yes I agree launch lineups could be better, there should be at least 5 wanted titles available at launch, so people can choose which ones to buy and more should come out 1-2 months after (not 6 months between launch and the next release). Especially for those paying full price for the console. But unfortunately it does not work that way, for any console.