Just goes to show...
... how easy it is to spy on people. This was always the case, but now it takes a whole lot less effort, and it's getting easier and cheaper by the day. Look, even micros~1 is doing it.
There was a study not long ago by, if memory serves, a couple of Japanese researchers who could track people with reasonable accuracy around an office building with little more than strategically placed passage sensors. Which just goes to show that, well, a lot of things, really. Think about it.
If we don't really need (expensive, cumbersome, not all that accurate) electronic face recognition trickery behind ubiquitous CCTV networks to automatically track and even identify someone in an office building, then what does that say about our governments ``flight forward'' towards ubiquitous surveillance with the newest technology they can get?
Afterward we can resume our habitual bickering about the (un)necessity of tracking everybody at all.