Wii Sports quickly became the "killer app" for Nintendo's last-generation Wii. But, what will lure in the mass market to Wii U? Surprisingly, Nintendo of America president Reggie Fils-Aime says that the company's online offering via Miiverse could be it.

"I think that [Miiverse] will pleasantly surprise people," Fils-Aime told AllThingsD. "As the network grows and the installed base grows, it will prove to be a true killer application for the system, and I say this loving what we have done with Nintendo TVii and loving all the games. Until you try it and experience it, you may not totally understand it."

Miiverse marries aspects of services like Xbox Live and social tools like Facebook or Twitter. You can see what your friends are playing, share screenshots, ask for tips, and share your thoughts on a game. You'll also (eventually) be able to access the Miiverse through your 3DS, PC, or mobile devices.

Some rah-rah cheerleading for an impending hardware launch is normal, and it's not surprising that an outspoken Nintendo executive is playing up one of its new features. At the same time, much of Nintendo's online strategy for the Wii U is still shrouded in mystery. The Miiverse has some interesting ideas in its favor, but emphasizing its impact on the market is a bold move considering how much catching up Nintendo still has to do with other aspects of its online initiative.