Google is known -- by their own blog! -- to use this data for ad targeting. Until they say they aren't, it's more than reasonable to assume they continue to us

Google is known -- by their own blog! -- to use this data for ad targeting. Until they say they aren't, it's more than reasonable to assume they continue to use it for ad targeting. They are certainly aware of other ad networks using the search query string: employees have mentioned it in conference talks. If they were using no more information than any other ad network has access to, it would be trivial for them to publicly say so. Until then, I suggest writing the FTC.