Even if you've been religiously checking in to Times Square, Foursquare has a gigantic reminder to do so. The social networking site squared off with other ads by displaying, "“Check in, find your friends, unlock your city,” which, according to TechCrunch is the largest digital billboard in Times Square. Will you be checking in soon?

The ad is up against a myriad of visual stimuli and it just may stand out. We wonder if tourists will take note and help spread Foursquare's presence back home? What do you think of the digital billboard?