What is amazing is where Facebook’s new members are based. The social network has tapped the United States and is focusing most of its efforts on growing overseas. A lot of Facebook’s growth over the past month has been in Brazil and India, two huge countries where Orkut, another social network, dominates. Orkut has more than 100 million active users, but nearly half of those are in Brazil, with another 40 percent in India. Only about two percent of the service’s users are based in the United States, which is why you may not have heard about it. What you have heard about, though, is Orkut’s parent company, Google, which should see Facebook’s move into its territory as a direct challenge.