Adwords in response to prior searches

[JonW]

Searched on "HIV facts" a saw an ad for famous diamond seller bluenile.com.

Previous search (q-1) was "diamonds"

Will we soon see ads for searchs (q-2, q-3, ...), and wouldn't that be a way to build a web-scale profiling system that could target based on keywords and behavior profile.

[dpam]

Great point often forgotten. Yet another Google 'initiative' we have no control over. If you have visibility in queries, you'll see non-exact match queries for exact match keywords, presumably because of this.

It would be fine if advertisers could opt in and control it. But they can't.