As long as they have a good list of new aaa titles, Nintendo will be fine with the Wii U. By that time we should have some nintendo brand hot titles, monster hunter, bayonetta 2, and it looks like other developers are warming to the system as I'm seeing other new titles announced recently.
Something else to consider, you'll need pricey new extra controllers for them as well, so you have to add probably no less than $60 to their bases systems just for one extra controller. I'm guessing we'll see the ps4 ring in around $450-$500, and with a second controller, thats getting to be quite a bit more than even the deluxe wii U.
After seeing Tomb Raider on the ps3, they are really going to have to show something more than the demos we saw for us to upgrade our ps3... I saw nothing better than what I saw in tomb raider, and if its not compatible with our current catalog, we'll be using our ps3 for our current backlog. I think we have 20-30 titles backlogged for our wii U and ps3 right now, and it'll take us months to burn through these.
And we'll be picking up 2013 titles around christmas at the usual deep discount pricing, so we'll have even more by then.
We popped for the wii u launch, but I think we'll be sitting tight on the ps4 and xbox 720 for no less than 6 months after launch to see something that really compels us to go with one or the other.