kaz - 10:55 pm on Jan 10, 2010 (gmt 0)

Did you consider that the ads you see may be different from the ads your visitors see. For example, if you looked at the NexusOne phone on the google site you may be seeing the ad based on that visit and personalized ads. So maybe it is a case where google is serving the ads that are best. Even if you don't realize it. Others may not be seeing the NexusOne ad - if they haven't visited the nexusone site ... while others maybe - if they have visited the nexusone site.

Considered the impact of serving personalized ads before filtering imo