So what is new and different?
Product Listing Ads
Product Listing Ads (PLAs) have grown and evolved since they were introduced in 2010. Google has tested new formats over the years and allowed these ads to take up more prime real estate on the page. In 2012, Google began using the format to monetize the previously free Google Product Search listings under the Google Shopping moniker.
Below is a SERP page view before Google Shopping became a pay-per-click model. Notice PLAs and Google Shopping in separate spots on the page, the former being pay-per-click and the latter being free traffic.
And, here is a 2014 look at PLAs. Notice how the PLAs push the organic listing down the page, taking more landscape for paid traffic and making money for Google (with an added ‘Sponsored’ note to label these paid ads). In addition to top placements, Google often serves these Product Listing Ads on the right rail.
Enhanced Sitelinks take up even more valuable space on the page than traditional Sitelinks by allowing advertisers to assign ad copy to their links. They also more closely resemble (site)links in the organic listings below. (The pink background on the paid ad helps differentiate the two listings.)
Image Extensions look similar to Google Image and Shopping results. These visual ads also take up more space on the SERP. It’ll be interesting to see if Google rolls out this ad type more widely in the future.
App Extensions allow users to quickly download an application on their mobile device. The download option can be seen in paid or organic listings. Notice the clickable application images in both the paid and organic listings in the mobile screenshot below, pointing to the app download page.
Social Extensions pull in the Google+ results, which are often found in the (organic) Knowledge Graph on the right rail as well. (This SERP conditioning article by Ben Goodsell at RKG outlines more detail about how these right rail SERP components - Google Maps, Knowledge Graph and PLAs - are taking traffic from organic links.)
Speaking of the Knowledge Graph, what about ads serving within the Knowledge Graph, something Google is testing now. This would definitely further blur the two spaces, and monetize the free right rail landscape on the SERP.
Resembling Google Product Listing image results, Google’s Carousel actually flips the SERP results on their head, by putting organic results above paid ads. Here is a look at the Carousel results:
When a Carousel image is clicked, the SERP page is auto-regenerated with a query related to the listing. In the example below, the first ‘Omni’ hotel was clicked, showing ‘Omni Dallas Hotel Dallas, Texas’ search results with both paid (two top-placement ads) and organic listings (Knowledge Graph with business information & another organic listing) below the Carousel images: