Foursquare is now signing up over 22,000 users a day according to PlacePunch, a marketing agency that tracks Foursquare statistics.
At this rate, PlacePunch projects that Foursquare will reach 10 million registered users on July 9, 2011.
Foursquare’s growth appears to be accelerating, if this chart is to be believed.
It’s been widely speculated that 2011 will be the year that mainstream users start adopting location-based services in earnest as people decide apps like Foursquare are useful, not creepy. It may also drive sales for the first published book about how to use Foursquare, which came out Monday.
Foursquare’s 6 millionth user, Pierre B. in Paris (do they call it Quatrecarrés?) registered yesterday. He has not unlocked any badges yet.
ajeffries [at] observer.com | @adrjeffries