Foursquare Labs Inc., a New York mobile social networking startup whose $1.35 million first-round financing in September was the most competitive in recent memory, may be the next big hit on the Internet, say many tech entrepreneurs and investors. But beyond buzz, what is Foursquare, how does it plan to make money, and why did it choose O'Reilly AlphaTech Ventures and Union Square Ventures from among the many investors clamoring to back it? To find out, The Deal asked Foursquare CEO Dennis Crowley, the former co-founder of Dodgeball, which Google Inc. (NASDAQ:GOOG) bought and subsequently deadpooled, for a behind-the-scenes tour. Watch the video below or download it on iTunes.