Today I experienced the Beckham Effect firsthand. Two people called into the salon to book appointments, saying, "I want a whole new look. I want the Victoria Beckham hairdo." Ah yes. (A girl I work with already has the Victoria hairdo.) If two women are spontaneously changing their hair, and the Beckhams have only been here one day, multiply that by two girls at most salons across America.
My Beckham Effect prediction: we'll be seeing more of Posh's hair than of Beckham's jersey.