Seems that there may be some movement with Adsense on personalised adverts. These seemed to be compulsory for a while and only the end users could opt out. The settings in the Adsense control panel didn't really have much of an effect. Now it seems that Google has allowed publishers to opt out of peronalised interest ads. It has renamed the section (Allow & Block Ads > Ad Serving) to "User based ads". It apparently does not affect remarketing.
One of the advantages of the early days of Adsense was the contextual nature of its advertising. Earnings were higher then but it was a bit of a bubble economy at the time. The whole personalised advertising thing seemed a bit iffy because there are reports of people seeing the same targeted adverts weeks after making a purchase. It seems that the people responsible for this idea (think it was a bought-in product rather than a Google developed product) didn't take the shopping/purchase loop into consideration.