ZocDoc is a service that allows users to sign up for doctor appointments online in New York City, NY.  As ZocDoc plans to expand their online services to other major cities, Amazon.com, Inc. (NASDAQ:AMZN) CEO Jeff Bezos and salesforce.com, inc. (NYSE:CRM) CEO Marc Benioff have come together to invest an undisclosed amount in ZocDoc.  Bezos’ investment came through Bezos Expeditions.

Last month Vinod Khosla’s investment arm, Khosla Ventures led the investment of $3 million Series A in ZocDoc.  ZocDoc did not disclose how much this round of funding was, but it is “in the ballpark” of the Series A [SAI].  ZocDoc’s founders include Nick Ganju, Cyrus Massoumi, and Oliver Kharraz, M.D.  ZocDoc plans to make revenue from advertising and charging a nominal fee to practicioners.

The site has rough 50,000-60,000 users.  ZocDoc also turned one years old today.