This is a good start

Google is reducing the length of time it retains personally identifiable search data from 24 to 18 months. It's a response to pressure from privacy advocates and European governments. As I've written before (Is Google a threat to e-health?) a full search history could reveal a heck of a lot more about a person than even full disclosure of their medical record. Even if Google doesn't do anything evil with it, that's not to say someone else couldn't get hold of it and do some. My concerns are not eliminated with this latest move but they are reduced a bit.