I don’t think it’s any shock that Google has the data to segment users based on their browsing habits. The shocker to me is that they’re making the result of that segmentation available to webmasters everywhere.

The full text of the email is:

From: Google AdSense
Subject: Introducing interest-based advertising – action required for your AdSense account

Hi,

We’re writing to let you know about the upcoming launch of interest-based advertising, which will require you to review and make any necessary changes to your site’s privacy policies. You’ll also see some new options on your Account Settings page.

Interest-based advertising will allow advertisers to show ads based on a user’s previous interactions with them, such as visits to advertiser website and also to reach users based on their interests (e.g. “sports enthusiast”). To develop interest categories, we will recognize the types of web pages users visit throughout the Google content network. As an example, if they visit a number of sports pages, we will add them to the “sports enthusiast” interest category. To learn more about your associated account settings, please visit the AdSense Help Center at http://www.google.com/adsense/support/bin/topic.py?topic=20310.

As a result of this announcement, your privacy policy will now need to reflect the use of interest-based advertising. Please review the information at https://www.google.com/adsense/support/bin/answer.py?answer=100557 to ensure that your site’s privacy policies are up-to-date, and make any necessary changes by April 8, 2009. Because publisher sites and laws vary across countries, we’re unfortunately unable to suggest specific privacy policy language.

For more information about interest-based advertising, you can also visit the Inside AdSense Blog at http://adsense.blogspot.com/2009/03/driving-monetization-with-ads-that.html.

We appreciate your participation and look forward to this upcoming enhancement.

Sincerely,

The Google AdSense Team

Email preferences: You have received this mandatory email service announcement to update you about important changes to your AdSense product or account.

Google Inc.
1600 Amphitheatre Parkway
Mountain View, CA 94043

One thing that has me thinking they’re less than purely evil is that they at least show you what they think you are in your personal ad preferences page, and allow you some options for configuration. However, it would take someone reasonably savvy to locate that page.

I’m interested to see where this goes. I know it’s a big win for businesses that want better ad targeting, but this is clearly a big setback for privacy advocates.

Regardless, I really can’t wait to see the ad profile they assign me… . o O ( Computer nerd, mountain biking, porn addicted, binge drinker )