At this point Nintendo just needs 3rd party games which simply aren't coming. People still want Nintendo games, they just don't want ONLY Nintendo games.
I say this as a happy owner of the Wii U and 3DS. Zelda may still push a few consoles and people may buy it as their second system going forward, but I can't see them improving their standing in the console wars going forward without 3rd party support.
Got a little off topic there but that's just what comes to mind every time I see a "Could this game help Nintendo?" thread. Nintendo the company is fine (despite the success of the PS4 I imagine Sony is looking on Nintendo's situation with envy), but the Wii U seems fairly cemented as the least desired console of the three this generation (though it's currently my personal fav of the three), and I doubt any Kirby game will help that much.
That reminds me, I need to preorder the coming Kirby game :)