On-body tagging

Interesting US Patent (7,602,301 - link)
on a system to record human movement based around on-board sensors, and then uplinking via cellular or other networks. To me, one of the intersting aspects, particularly in terms of activity tracking is the degree to which already installed sensors and tracking devices along with existing infrastructuctures can support it. This is already a commonplace in terms of cell-phone tracking, but I just got to wondering if what we will end up tracking is people's things, not them. For example if exoskeletons (http://www.gizmodo.com.au/2008/10/hal_robot_exoskeletons_available_for_rent-2/) catch on, tracking their ;location and settings and hence inferrring activity should be trivial.