After a little more education, our new estimate is that it’s between $6 million and $6.5 million, and that its investors — Union Square Ventures, O’Reilly AlphaTech Ventures, and some angels — picked up about 20% of the company for their $1.35 million total investment.
This makes more sense. Foursquare has good buzz, and received interest from several VC firms. But it’s still small — about 40,000 registered users, and little (if any) revenue. It’s currently working on a BlackBerry app and hiring another developer.