I predict—and I say this as a long-time Nintendo fanboy—that Donkey Kong Country Tropical Freeze, watch_dogs, Assassin's Creed IV will not cause consumers to go out and buy a Wii U and that Super Mario 3D World will only provide a short-term increase in sales.
If a 2D Mario game is not enough of an incentive to buy a Wii U, why would a 2D Donkey Kong game be?
The Ubisoft titles could be had on every other platform, and consumers are going to choose the version that their friends are playing or has an incentive for them to do so (i.e. better graphics). As evidenced by Nintendo's failure to convince consumers otherwise, for the large majority of the market, Off-TV Play is not a compelling enough feature and thus would not purchase the Wii U version solely for Off-TV Play.
Super Mario 3D Land was able to increase consumer awareness of the Nintendo 3DS, and I expect it to do the same for Wii U. However, Super Mario 3D Land was quickly followed up with Mario Kart 7 and Monster Hunter 3G (in Japan) to allow the momentum of a 3D Mario action game to continue through the holiday season and into 2012. Super Mario 3D World should have launched in November; by December, a large section of the market would have already started or completed their holiday gift shopping. In other words, the Wii U did not have the 3D Mario action game momentum in November.
Due to the absence of any major software titles between Super Mario 3D World and Mario Kart 8, there will be a lull in sales between the releases and thus Mario Kart 8 would have to recreate momentum for Wii U instead of growing the momentum created by the 3D Mario action game.
Wii Fit U and Wii Party U does not largely appeal to the consumer who is actually going to be buying a Wii U this holiday season. These games were bought on Wii by consumers who had felt that motion controller gaming was something that they liked, and thus wanted to continue that experience with Wii Fit and Wii Play. Leaving aside the fact that "casuals have moved on", there is no title to build momentum for Wii U for this market. There is no new experience for this market to cause them to buy a Wii U in the first place.
I strongly feel that Wii U will be Nintendo's worst-performing platform (with the exception of Virtual Boy and Nintendo Color), with respect to both hardware and software. This, inevitably, would lead to large scale changes at Nintendo, including senior management and corporate philosophies. I also expect that Wii U will not be Nintendo's last home console, and that they next one, created with new management, philosophies and a restructured Nintendo Co., Ltd. would create a new home console that is as paradigm-shifting as the Wii but as aggressive as the PlayStation 4. I feel that this company, lately, has become too "Japanese" that is adversely affecting global operations and sales, and that this will be rectified for the next generation.
However, they face two issues should they discontinue the Wii U prematurely:
1. Nintendo will risk to lose significant mindshare for their home console space for consumers, retailers and developers should there be a large gap between Wii U being removed from the market and the next home console arriving in the ninth generation. This is akin to the Blackberry 10 being too late to the iOS/Android party. The developers have moved on. The consumers have moved onto iPhone/Android. Blackberry retail presence has been miniaturized.
2. Nintendo will risk another Wii U/Dreamcast situation should they launch a new home console, comparable to or better than the horsepower of PlayStation 4 and Xbox One, in the middle of the eight generation. By the time the console is on the market, PlayStation 5 and the new Xbox will already be nearing announcements. These competitors then have the significant advantage to make their products more powerful than Nintendo's offerings.
Nintendo's only solution now is to hold off on the Wii U, as they did with Gamecube, as they prepare their Nintendo Revolution 2.