We do know what the product won't be, though: it won't be anything like the Fitbit or other popular health monitors. And it doesn't seem to have anything to do with the Wii Vitality Sensor, an ambitious project the company introduced in 2009, only to later abandon as it couldn't get the technology to work to its standards.
Iwata was the internal champion of that device, which tracked a user's pulse and stress levels through light pulses in the finger. One possible gaming application he showed off privately in 2009 had the sensor helping train users how to breath in a more rhythmic fashion.
But just because the Vitality Sensor is dead doesn't mean some of the ideas behind it won't work their way into this new product.
"There have got to be a [significant] number of people under stress who really want to release that stress, but those people are always running out of time," Iwata said in 2009. "I think everyone in this room has experienced [the situation where] you are tired and want to go to bed, but can't because your brain is tied up."
Pachter, though, said that the announcement is just a way to resurrect Wii Vitality Sensor tech.
(Read more: Nintendo slides by almost a fifth after loss warning)
"This is a great example of Nintendo having a formula and not deviating from it no matter what. The formula was: 'We tried the Wii Vitality Sensor and it didn't work and we canceled it. But let's not scrap all that work.' ... I think [Iwata] is hoping not to lose all that sunk cost in it and wants to exploit it."
Fitness has meant big money for Nintendo in the past, so it makes sense that it's chosen to pursue it further. The Wii was praised for getting gamers off of the couch—and the Wii Fit franchise has sold more than 43 million units life-to-date.
As it did with the Wii and hand-held Nintendo DS system, Nintendo is relying on its "blue ocean" strategy—which boils down to avoiding a feeding frenzy for a small customer base (aka a "red ocean") when there's a much larger, untapped one available (the aforementioned "blue ocean").
Moving into an unproven space like "nonwearable" fitness tech might sound crazy now, but in Iwata's mind, it beats following the pack.
"Once a blue ocean has established the status of a new marketplace, eventually the blue ocean turns red," Iwata said in 2009. "We have the greater potential to create the blue ocean market when people are skeptical. So when we realize that other people are coming into [a] market ... there are two things we [can] do. One is trying to intensify the fun nature of something we are already doing. The other is try to create a new blue ocean."
"Even if it is revolutionary, sooner of later people become tired of a new form of entertainment," Iwata noted in 2008. "This happens faster when others try to reproduce what was fresh. For all of us in the video game industry, there is danger in standing still. We must find more ways for players to become engaged, even with interactions we would not call games."
And while fitness tech is the rage now (and arguably, is a current blue ocean), Nintendo's product is likely two or more years out. A lot can change in that time, given the fickle nature of consumers.
—By Chris Morris, Special to CNBC.com.