Google is a sharp cookie

Google is now willing to tell you what they know about you. Visit the ad services preferences to find out what they know about you.

The cookie is in doubleclick.net domain, by the name id. It has a unix timestamp in it, which should show you how old your cookie is. They expire it after 1 year.

This is a good initiative on the part of Google, but here is the bit that's scary.

My cookie expires Jan 16, 2012, which means its barely a month old. In this period, they have been able to figure out that I am interested in Advertising and Marketing, Computer & Electronics->Programming, Software & Computer Security. Of course - their score is not 100%, but based on what I did during last month, thinking that I am interested in movies (I purchased a ticket for Avatar from AMC Entertainment) and Watches (I bought a few), they are close.

Too close for comfort. Would I opt out? No. But the average user might.