Barack Obama commands respect while Hillary Clinton overacts. Plus: John Edwards' disappearing act, Mary Shelley debunked, and Ann Coulter's gender weirdness. Nerves, nerves, nerves: The contenders in both parties for the 2008 presidential nomination have been acting like skittish race-track thoroughbreds rearing and shying as their handlers try to shove them into the gates. Each campaign is super-concerned about its candidate getting distracted, winded or making a crippling misstep. What in tarnation was the Hillary Clinton camp thinking when it threw a tantrum about Hollywood producer David Geffen making a few critical remarks about her to a fagged-out media scold?...