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Google will now verify if you're a human by turning on your webcam and asking you to wave your hand
(docs.cloud.google.com)
This is a most excellent place for technology news and articles.
Calling it: In the future we will learn that they have been using it to gather face recognition data and have been using it to track their users in the real world by partnering with the likes of Flock.
Reasonable bet if they didn't already have root on devices in people's pockets, with cameras pointing at their faces for hours per day. Along with GPS, cell, WiFi and Bluetooth location services.