Google is offering a plugin that keeps the optout cookie on your computer even if you clear cookies. This thoughtful chap took a look at the source code and reports:
After examining the source however, it seems that all the plugin does (at least in Firefox) is check to see if the cookie is there when you load the browser. If the cookie is not found and third party cookies are not disabled, then it adds the opt-out cookie.
It will be cool to connect the opt-out db with this.
(Hoping (in sort of a lazy way) that the component that checks for the presence of the Google cookie may be a sufficient indicator of whether to run the entire sequence of opt outs.)
UPDATE: I think we’ve learned now in our own handling of the Google cookie that it doesn’t look at all at cookies that are present. It simply re-writes the hardcoded opt-out cookies upon certain events (new session, cookies being cleared, regular interval).