Google will buy local business reviews site Yelp for at least $500 million, according to TechCrunch.
The search giant is already building a directory of local businesses with its Place Pages, which makes use of its maps and local search tools. Yelp already has data on this and ratings and reviews of local businesses from users.
As media blogger and author Jeff Jarvis points out via Twitter, Google can strengthen its positioning in the local advertising market and has spotted an opportunity in online communities around local business that other media, including newspapers, may have missed.