Sports U

A stellar first party game that everyone is talking about (better on WiiU but if they get a Mario Galaxy level game out on 3DS it'll be big too) coupled with a price drop before their launch could get people really talking WiiU and Nintendo before their launches but there's only so much you can do when it's the first leap in power in 8 years (WiiU was more of a small step though big from Wii I'm talking industry wide advancement...on consoles).

Honestly, nothing. I don't see Sony or MS doing anything as of yet that will allow them to appeal to the Wii market. Nintendo doesn't really need to worry about what they're doing, but focus on what made the Wii a success. Novel experiences with broad appeal, excellent exclusives, and local multiplayer.

Release some god-dang games already.

Well, the WiiU has the lead already,

They said they would be showing off smash bros and 3D mario this E3 so I think that will help a lot.

The biggest thing for them though is gonna be 2 things:

1) price cut, it will probably come either at E3 or approaching christmas. People are hesitant on buying the console because they feel that a price cut is imminent and don't wanna be pissed off that they didn't wait.

2) Sony and Microsoft's consoles have to have their images deflated. Microsoft has already started with all of its DRM crap. In response, amazon already reported that Wii U sales went up 800% as of the console debut. However people still hold out hope and still think that either of the two consoles could beat the pants off of the Wii U. Once E3 is over Wii U sales will almost certainly go up provided that neither of the two have a truly amazing E3.

Look at the sales numbers. MS and Sony haven't been able to sell not one copy, heck sony is selling us an invisible consle. 

Based on rumours, they've already got it all lined up.

Mario Kart (sold over 33 million on Wii)
Wii Fit U (sold somewhere between 23 and 44 million on Wii)
3D Mario (sold around 11 million and then 7 million on Wii)
Zelda (Wind Waker HD) (sold 7 million and then 4 million on Wii)

and from vaguer rumour,
Wii Sports U (sold 32 million even with the mostly non-bundled version, Resort, on Wii)

Nintendo will do fine this holiday despite the launch of competing consoles, because the Nintendo faithful who haven't yet gotten a Wii U will likely have gotten one by the end of the holiday season (or soon thereafter). There are some millions of guaranteed Wii U customers that are waiting for the new 3D Mario, a new Zelda, the next game from Retro; Nintendo should have enough heavy-hitters lined up for the holiday season to start winning those people over.

What Nintendo needs to worry about is 2014 and beyond. Nintendo needs its traditional franchises to bring in more than just the traditional Nintendo gamer, and it needs some serious 3rd-party support in order to keep its lineup from being too sparse. A big casual hit would be nice as well, something that absolutely convinces people that a tablet-controller is something they MUST have. Nintendoland was supposed to be that title, but it fell short; Wii Sports U is likely the next candidate up to bat.

First its no controller, now its no console?! What could define next-gen more then the PS4!!!