leadegroot - 11:57 am on Apr 28, 2007 (gmt 0)

I see similar things. I have two sites, lets say one is about, umm, rope climbing and the other is about, says, hairdryers.
Rope Climbing is older and *since I started the hairdryer site* (October, IIRC) I sometimes see ads for hairdryers on the rope climbing site. Never before then.
There is no overlap between the two topics, beyond everyone probably wants a hair dryer at some point.

I have wondered if this is personalisation, or mistargeting due to a common adsense account.
No way to know.