I was just commenting on General Grant post at http://forums.digitalpoint.com/showpost.php?p=94266&postcount=6. That sparked a little data analysis exercise - as follows: We run google adsense as a publisher, on two of four sites we have in the co-op. Those two sites are responsible for 55,000 out of 60,000 weight. In the month of January, we delivered 250,000 impressions for the co-op members' ads we carried on our sites. Our adsense stats for the month: 26/31 days carried google ads Effective CPM (according to google) $4.25. Adsense gets decent positioning obviously, vis a vis the text link ads for co-op members. But all in all - foo for thought. What weight do you heft? How many impressions does that weight deliver to the co-op?