The market has never supported three viable 'hardcore' platforms. And for the most part, the days of saturating the entire market with one franchise on everything are over. Granted that there will still be Madden and Call of Duty, big franchises that they want on everything, but there's no Acclaim's or Midway's anymore to just drop NBA Jam or NFL Blitz on every system with a pulse.
There's a reason these companies are going out of business and losing money. Bigger budget, bigger resources needed, opportunity cost with every move. What should companies like DICE do - waste resources that could be used to start working on the next iteration to make a Wii U game that's won't sell near as good as other platforms?
"That's good sales ... for Wii U" isn't good enough to justify games. When Zombii U comes out and it's only done around 150K or so LTD, that's not enough. Games need to do Nintendo numbers, and they're not.
3rd party games haven't done well on Nintendo since at least the Gamecube generation. The only thing that drives sales on Nintendo platforms are Nintendo games themselves. The last time there was a 3rd party game that was a system seller for Nintendo was probably during the Street Fighter II era.
Nintendo will do just fine. Their business plan of producing everything for profit is more sustainable. If the Wii U only sells through 20 million units (which it wont) in its life time like Gamecube did - it will still be profitable for Nintendo. And they still have their loyal domestic Japanese market. Nintendo is a bit like Apple in that they sell their hardware for a profit and there is enough differentiation between their own product and everything else on the market. You buy a Nintendo console to play Nintendo games.
The real loser this generation is gonna come from either Microsoft or Sony. The majority of the games people play on these systems are multi-platform. And there's a lot less to differentiate these two in terms of what they offer.
This coming generation Sony and Microsoft are gonna duel to the death, probably making huge hardware losses and all whilst dealing with increased costs of producing AAA games - which will mean even lower retail margins. Sony might bow out, they are struggling in every other tech industry they are in (phones, tablets, TVs, computers, laptops, mp3 players etc) and they were losers for the majority of the past console generation. And they're coming back on the PS4 with close to the exact same strategy as last time.