Once the 911 GPS protocal is in place, do you REALLY think that it will not be used to track fugitives, suspects, "enemies of the state" etc? Really? I have a nice bridge to sell you.
I'm cynical enough to expect that it's just a question of time before there are facial-recognition cameras virtually everywhere, recording every "anonymous" face they see. Although the faces will be "anonymous" they will nonetheless be collated, i.e., "anonymous_face_q892828" will have an "audit trail" of every camera it's been spotted by, with each entry timestamped. Eventually, "anonymous_face_q892828" will be in a venue where he's not anonymous, and voila! -- a name is attached to the formerly anonymous ID entry, and that person's entire past travel history will be there for the viewing.
Since the inception of cell phone service, it's been necessary for each tower to know "who" you are. When a call comes in, it goes to the tower you were last closest to, rather than going out to all towers. The way it "knows" (or assumes) you are there is because that was the last tower your phone registered with.
When you turn on your phone, it registers with the nearest tower. It will periodically re-register, and, when you travel to another tower's range, it will register with the new tower. So, as long as you've been within range of at least one tower, and your phone's been powered up, there is a record of (roughly) where you were, and when you were there. (This is how the "legacy" cell phone system has been working since inception.)