I can’t believe we’re going through this again. In January 2005, Time magazine featured on its cover a photo of a young man in a shirt and dress slacks sitting in a sandbox. The headline: “They Just Won’t Grow Up.” The article featured the research of one Jeffrey Jensen Arnett , PhD, a developmental psychologist who coined the term “emerging adulthood” to explain these puzzling, infantilized adults. The cover story of the New York Times Magazine this weekend, already situated snugly at the top of the Most-Emailed List, is a near-exact repeat of this story from 5 years ago, this time asking “What is it About Twenty-Somethings?” Again Arnett is the resident featured expert. The Times’ only innovation, besides the slightly higher quality of the writing and the greater length, is tarting up the article with lots of sexy pictures of 20somethings (“I’m lying on my bed, all angsty! Look down my shirt!”) so readers can lust after them while simultaneously shaking their heads. [. . .