I’m still a bit unsure as to whether this story is a bit of a furphy, or not. It seems that Google is testing ads “in between organic results” (shock, horror, and doing what the rest of the internet has been doing for the last 15 years).
Google organic SERPs have pretty moved to infinite scroll, where there are no more 10 results to a page and then you click the next number in the bottom set of blue links, but instead you scroll endlessly looking for that unicorn amongst the dross. In doing this, it lost an ad spot at the bottom of the list, and other navigational / promotional spots under the Next Page links.
If there is no intra-page delineation, the only thing you can do if you have lost an ad spot is to re-inject it. With the mess that is now Google Organic SERPs pages, it’s very hard to know *where* the ad injection should or is. Google moved away from the 10 blue links a long time ago, so it’s no longer after the 10th organic link, but might be after the second People Also Ask, and so on.
For once, I’m neutral on this. I see it as a result of infinite scroll, re-injecting ads into spots where they previously would have been, rather than squeezing ads in places where they weren’t before. And as I said, the rest of the internet has been doing it for a long time.
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