In a recent question-and-answer session with investors, Nintendo prez Satoru Iwata gave a few reasons why the Wii vitality sensor was never actually released. For one, in testing it didn't work on everyone, just 90 percent of folks. That, apparently, was not good enough.
In case you don't know what this thing is, the vitality sensor was a fingertip sensor that checks your pulse and "a number of other signals" coming from inside you (?) to do something or other. Another problem they had, according to Iwata, was figuring out what to do with it.
"The Wii Vitality Sensor is an interesting device, and we did various experiments to see what is possible when it was combined with a video game. But, as a result, we have not been able to launch it as a commercial product because we could not get it to work as we expected and it was of narrower application than we had originally thought."
Iwata did say, though, that if the tech improves enough so as to increase the working rate of the device to 99.9 percent, then they'd probably start selling it anyway. As of now, though, the vitality sensor is in a "pending" state, which means they aren't doing anything with it now nor are they planning to do anything with it.