They get big hugs for sharing this with us.
Google is our primary ad provider. They regularly use cookies to track users’ interests on our site, other sites they visit where Google is the ad provider (most sites on the Internet), and based on what Google searches they perform.
If users would like to opt out of this kind of tracking, which Google uses to server “better”, more targeted ads to them, they can do so using the opt-out tools that Google provides. It’s not something we can do for them.
For more info:
http://www.google.com/privacy/ads/
To opt out of tracking by Google, and most other ad networks:
http://www.networkadvertising.org/managing/opt_out.asp
For a more permanent opt-out solution (the previously linked method will need to be re-set if a user clears all their cookies), please direct them to:
http://www.google.com/ads/preferences/plugin/index.html