Google wants to leverage the real estate publishers have allocated to display their ads by giving readers more ads at their option. Have you noticed the little < > arrows? They will let you scroll to get more contextually appropriate ads to click on. With click through rates falling rapidly, Google needed to come up with a boost to keep revenues growing.
Implications - Advertisements are abundant in contemporary society and, as these extend ads demonstrate, space is limited. Corporations looking to get noticed should consider alternative approaches to publicity, in terms of both creative content and location. A scroll for more ad may be lost due to numbers, but a large-scale publicity stunt could garner more attention.