I was wondering about the same thing. The article is extremely enthousiast about Foursquare, which I had stopped to use over Facebook. Foursquare adds a gaming

I was wondering about the same thing. The article is extremely enthousiast about Foursquare, which I had stopped to use over Facebook. Foursquare adds a gaming layer to check-ins, which tends to get boring with time. Facebook however adds its social layer, with the ability to passively say "Hey I'm there", and actually be read by people who might care.