Mr. Fox said that Google’s approach was different from what Yahoo, AOL and others call behavioral targeting. Those companies look at what a user did a few days earlier to show them ads about the same topic today. Google says it believes that search engine advertising is most effective if it relates to what the user has most recently searched for.
“We are trying to understand what the user is trying to do right now,” Mr. Fox said. “In some cases, those queries are ambiguous, so you need a little more context.”
Google Tries Tighter Aim for Web Ads - NYTimes.com
Google being smart yet again. This is what everyone should be doing.
In the same way that if I'm reading the sports section of the paper, I want to see ads about golf balls, I don't want to see ads for photo equipment when I'm searching for movie times.
Cheers to Google.