Are young women losing something by participating in casual hookup relationships? Laura Sessions Stepp, a prize-winning reporter for The Washington Post, has looked into the hookup culture, how it works, and how sex is becoming the primary currency of social interaction. We’ll talk with her this hour about her work and her new book “Unhooked: How Young Women Pursue Sex, Delay Love and Lose at Both” (Riverhead Books, 2007).