Google is currently in negotiations to acquire the local review site Yelp for a reported $500 million, according to The New York Times.
Yelp's sponsorship ad model is likely the main draw for Google. For a price, businesses can advertise on top of search results, create slideshows, and prevent competitors from advertising on their page.
Local businesses have been on Google's radar for a while now; recently, it expanded business profile pages to include maps, hours, and reviews from other websites. In June, Google gave the power to businesses to manage their profile pages in search results. In addition, Google has been trying to create simpler ways for small and local businesses to advertise on its search engine.