As Greg Sterling points out, in this case Google is playing catch-up with sites like Ask.com (which launched this in December with its AskCity local search tool, as well as Trulia and Yelp. Yahoo has defined neighborhoods in large cities for some time as well.
Optimising Digital Marketing Campaigns with Search, Social and Analytics
At SES London (9-11 Feb) you'll get an overview of the latest tools, tips, and tactics in Paid, Owned, Earned, Integrated Media and Business Intelligence to streamline your marketing campaigns in 2015. Register by 31 October to take advantage of Early Bird Rates.