Dennis Crowley, co-founder of Foursquare, and Alexa Andrzejewski, founder of Foodspotting, are the hottest people in location-based services. Foursquare has a million users. Foodspotting has 100,000. Both are growing very quickly and getting lots of attention. I sit down with them at the Big Omaha conference and talk with them about the location-based service business. In the interview Dennis tell