Google has removed the ads from the right hand side of search results as well as increasing the number of ads at the top of some search queries to 4. In my opinion, this is the biggest shake-up of search results since Google reduced the size of the map pack earlier this year. It will be interesting to see how this will affect traffic.
Google is switching up how it displays ads on desktop searches, removing them from the right-hand side of results and putting them only at the top and bottom of the page. The change was first reported by The SEM Post with Google later confirming the move.