Alternative exercise - the Wii as therapy

It seems the sales of the wii are being driven in part by adult living facilities buying them as therapeutic instruments for seniors. A case of dual use technology, or a creative design choice by Nintendo. What will be interesting as wii usage becomes more sophisticated in this realm and we see socials taking place over the internet where inter-nursing home leagues will sprout up. I am hoping that the system  and future systems will be sophisticated enough to engage seniors in real calculated physical therapy comparing metrics of improvement.