You may be wondering why most online ads are now displaying “AdChoices” instead of the “Ads by Google” text. AdChoices is a new addition to Google AdSense and many other advertising networks. It is there to inform you that interest-based targeted advertising practices were used in deciding the ad served to you. The icon will normally be placed at the top right of each online advertisement. Upon clicking the “AdChoices” button, you are directed to What are Ads by Google? It is no surprise that it was coming (see the official AdSense blog post here), so don’t be alarmed when you see it on your existing AdSense ads.
You may find it surprising how accurately Google is able to determine your interests based on your browsing history and past google searches. Upon adopting the Adchoices initiative, Google allows you to view and modify the list of categories tailored to you in its Ad Preference Manager.
Chances are the categories on the list you see will be very close to your interest. This goes to show how effective targeted advertising can be.