This is the reason why I can't believe we're not all on IPv6 yet. You would think that the online advertising industry would have done everything in their power to push IPv6, at any cost. 90%+ of people on IPv6 will literally have a unique identifier FOR LIFE on every device they own. Marketers can now pinpoint down not just to an IP address that identifies a single NAT interface, but each individual device.
I hope that operating systems and/or routers will provide the option to rotate each IPv6 address on a routine basis. It would also be nice if ISPs would rotate the block that is handed out to each customer, but this is unlikely to happen. Every phone, every tablet, every PC, every thermostat, every door lock, every fridge... uniquely identifiable from the day it is hooked up to a network. :(