PS4/720 will be fine.
They have all the third party support in the world from every major publishing house and they will get all "dudebros" franchises and probably a ton of easy PC ports now too (see: Blizzard at the PS4 event ... why? Because PS4 is basically a PC box, 720 is likely the same). Bungie's Destiny coming to PS4/720 early on for example, Star Wars 1313, the best looking console versions of Watch Dogs, Battlefield 4, Call of Duty Modern Warfare 4, etc. guauruntee a great launch window even without a single MS or Sony 1st/2nd party game.
The Wii U basically has Nintendo and very little else. Platinum Games is good for 2 titles it looks like, but they're also working on PS4/720 (?) it seems.
Plus the XBox/Playstation audience is more of the 16-40 year old male gamer that has more disposable income and is more likely to buy on day 1 as long as there's a new Call of Duty or Battlefield or whatever.
They are not going to rely on soccer moms, grandpas, and 10-year-olds to sell their console early on (not saying MS in particular won't go for that audience, but several years down the line when the price point is cheaper). Nintendo's been abandoned by the casual audience because they don't behave the way regular core gamers do, they don't see the need to upgrade to Wii U (Just Dance is available on the regular ol' Wii or their XBox 360) and they are happy with $1-$2 games on their tablet/phone.







