Earlier quoted context omitted.
I can imagine a lot of applications for these types of systems: identifying undercover traffic police cars, finding whether someone is following you, identifying friend's cars (similar to FB's "Share your location") People would love such systems (and I'm afraid our privacy is gone for good).
This debate happens on HN again and again, but still: what privacy are you talking about in public space? Nobody has a problem with one person with a dashcam — why suddenly connecting these dashcams to a network that shares information is a problem?
Probably that bit