Foursquare users numbered 1 million in April 2010. As of of May 2010, Foursquare was adding 15,000 users per day. (Mashable) Foursquare was founded in 2009.
Sources of traffic to Foursquare in late 2009, early 2010: 24% Google, 21% Twitter, 19% Facebook (ReadWriteWeb)
36% of Fourssqure users are 39-49 years of age. (Quantcast)
63% of Foursquare site traffic is female. (Quantcast)
Projected valuation of Foursquare: $80 million (TechCrunch)
Gowalla users numbered 800,00 in May 2010. (International Business Times) Gowalla was founded in 2007.
Brightkite users numbered 2 million in February 2010. (TechCrunch) Brightkite was founded in 2005.
48% of Brightkite site traffic is female. (Quantcast)
"Positioning a product as the new cool, hip thing is great for getting people to flood in, but it's also going to make people flood out quickly as people move onto the next hot thing," Wharton marketing professor Jonah Berger says. "For a product to persist, at some point it has to transition from a hip new thing to something that has functional value." (International Business Times)