Regardless of whether they’re looking for it or just happen upon it, their next big thing might be Tumblr. They want more privacy and less bragging and can find it there. According to Adam Rifkin in a TechCrunch column: “Teenagers, amusing images, sharing only with trusted friends? In some ways, Tumblr is actually Facebook 2.0!” And “some data suggests that Tumblr may have already eclipsed Facebook as the most popular social network among 13-25 year-olds,” writes The Verge.