331,000,000 cell phones means that number of cameras watching your every move. No need for tin foil. This stuff is real.
http://diydrones.com/profiles/blogs/ted-talk-on-u-penn-swarming-quads-now-live
watch the vid sky net is almost complete
With that many cameras and that much data on their location/orientation, it is theoretically possible to have very close real-time surveillance of any place where cellphones are used.
Where there are many phones to collect data from, imagine something like a real-time, rotatable 3D image patched together from all the cellphone cameras. Any point in a public square can be zoomed in and listened in on.
It would surprise me if the CIA isn't at least developing such technology.