I've noticed that if I search for something on Bing, I see ads related to that search in Google AdSense on sites I visit later. Is this possible? Are Bing and Google somehow working together to share this information?
I don't like it at all. And once I've found what I'm looking for, I'm not interested in seeing ads about it for the next few hours or days. And that's the really big problem with interest based ads, other than being creepy. They very likely aren't relevant after the initial search.