I know you’re sick of reading three of these blog entries on three consecutive days but here’s what my Google Ads Preferences Manager has shown me today.
   I’m sick of writing about it, but Google’s being so damned predictable.
   First, the cookie is back, though it hasn’t picked up preferences yet this morning:

   Secondly, this is confirmed by the NAI opt-out web page, where, it must be noted, I have stayed opted out of every other ad network except Google’s, which evidently does not adhere to its privacy policies.

   A manual check of my cookies confirms that the Google opt-out one has disappeared, through no intervention by myself:

   Since I use Seamonkey on this system as well as Firefox, I’ve confirmed that the Doubleclick cookie on that browser is different to the ones shown above.
   I’ve discovered that my new Google opt-out cookie, obtained via NAI today and after I took the above screen shots, expires at the end of the browser session. Other NAI members’ cookies expire on dates anywhere from 2016 to 2041:

But look at the one I took a screen shot of yesterday: the expiry date is set to 2030. Where did it go? I never deleted it, and everyone else’s cookies are still in place.
   If you watch the Google video on the preferences, there’s no suggestion of the opt-out cookie being temporary (after 3’06”):

As we expected, Google’s Shuman Ghosemajumder leaves us with the impression that opting out is virtually permanent, unless, to quote his words:

If you delete your browser’s cookies, you need to reset your preferences, or opt out of interest-based ads again.

I have made no such choice to delete my cookies: I have done what an Average Joe does, and taken Google at its word.
   My laptop, however, has retained the opt-out cookie this morning (it hadn’t yesterday).*
   Conclusion: Google’s Ad Preferences Manager doesn’t work as promised. If you want to opt out of Google or Doubleclick ad targeting, you need to block their cookies altogether, manually. Or, based on my experiences over the last few days, pop into the Ad Preferences Manager every day.
   Google really needs to stop lying about its the Ad Preferences Manager, but then, I’ve come to expect this very behaviour from a company so arrogant about our privacy.

* PS.: One hour after writing the original blog entry, I revisited the Ads Preferences Manager on my laptop, and the same behaviour has occurred. The opt-out cookie has disappeared. All I have done on that machine in the last hour is visit YouTube. I had not ended any browser session in that last hour.
   The new cookie, again, claims to expire in 2030.
   Google’s claim that ‘Opting out of the DoubleClick cookie means that Google’s AdSense partners, DoubleClick, and certain Google services using the DoubleClick cookie will know you have opted out of the cookie and will not attempt to assign other DoubleClick cookies in the future. You will see the same number of ads as before, but they may not be as relevant when you opt out,’ is, therefore, untrue based on this test.—JY

P.PS.: On my laptop, despite increasing Firefox’s cookie limit to 65,535, the ‘2030’ opt-out cookie disappeared again—meaning that in the space of around nine hours, I had to opt out twice.—JY

P.P.PS.: Now tested over six days. The cookie keeps coming back.—JY