“The difference, though, is that site owners have to opt into the ad intents, instead of opting out.”
The Google App for iOS now turns words on other people’s pages into links back to Google Search. Publishers who object fill out a form listing every www, non-www, http, https and subdomain variant, then wait up to 30 days. Google’s own AdSense version of the trick is opt-in. Google sends a reader to your site and then plants exits back to itself, mid-antitrust fight.