Now Playing: 1-18-13 Marketplace Tech:

Yelp is partnering with cities around the country to put public data in their restaurant listings: health department ratings. The program is currently rolling out in San Francisco and in a few weeks will begin in New York, though some restaurant owners are nervous at the prospect. Realtors are launching their own "tech accelerator." And, new research suggests that spending time on Facebook may boost your self-esteem at the cost of your real world self-control.