While we don’t have any actual numbers yet from Facebook Places, it seems that Foursquare is stll the reigning king of the checkin. During yesterday’s annual Foursquare Day, the service saw its largest day yet, with 3,073,635 checkins according to a tweet from Foursquare founder Dennis Crowley:

Screen shot 2011 04 17 at 12.34.55 PM Foursquare breaks 3 million checkins on #4sqDay Oh Foursquare. It seems like only yesterday that we were reporting on the news of passing 1 million in a day. But it wasn’t just a great day for the Foursquare crew. Many charitable causes also benefitted. Taken from the Foursquare Day blog:

4sqday events collected food, donated money to Japan disaster victims, supported the Red Cross, Humane Society and much more. We love the fact that 4sqday helped contribute to these causes in a spontaneous, grassroots way.

A huge congratulations goes out to those of you who got your Foursquare Day badge. Plans are already in the works for next year’s event, which should promise to be even bigger. Until then, you can keep up with everything that’s hot in checkins and more right here on TNW Location.