Over the past six years there has been a range of tests on how Adwords are displayed. The final decision seems now to have been made, and this change will be immediate. Ads will only be displayed above and below organic search results. However, we may see four ads at the top of the page “For highly commercial reasons” says Google.
Google confirmed to Search Engine Land there will be two exceptions to this change; Product Listing Ads (PLA’s) which will appear either at the very top of the search result page or to the right, and ads that appear in the knowledge panel.
This change will bring search result display on mobile and desktop more in line with each other.