If it looks like a duck, and it quacks like a duck, we call it a dog so it's a dog.
MMOs are social networks too, wow.
Habbo is also a game, you play it with other people, you make a character, build rooms, interact with people. Playing with 25-50 people in a room in Habbo was often playing with a lot more people than in many "real" MMOs, you usually play as a group of only 5 in WoW separated off in your own little instance.