Just a quick thought after reading many posts with reference to google ads. I can't for one second believe that one side of google being the search side would wage war against the adsense model, simply because that's self destruction.
What I think is should we be taking a closer look at click through rates? What I'm saying is those with high conversion rates maybe deemed as poor content? Id be interested to hear if those that have dropped traffic whether the overall adsense click through were high?