Yesterday, Google has took the cover off its alternative to cookies named FLoC or Federated Learning of Cohorts. FLoC basically clusters "large groups of people with similar interests"," this is data gathered in the browser, not stored anywhere, and it looks at the group and analyzes that data, creating a hidden individual "in the crowd," Google said. It is the data from the wider cohort, "the crowd" of thousands of people that is shared, and that is then used to target ads to those individuals in the crowd.
Google said "FLoC can provide an effective replacement signal for third-party cookies." Adding that its "tests of FLoC to reach in-market and affinity Google Audiences show that advertisers can expect to see at least 95% of the conversions per dollar spent when compared to cookie-based advertising."
Google even made the code base for FLoC open for all to see on Github.
There is a lot of speculation and doubt about this in the WebmasterWorld forums. The admin in the forums said "Whether that changes things for the better of the user, IDK. Yes, it is very difficult even to make it anonymous. Google is voracious in wanting to track."
There is a lot of coverage of this news on Techmeme if you want to read more perspective.
