What is American Idol without the crankiness of Simon Cowell? Fans will have to find out, as the caustic British record producer announced in January that he would leave at the end of the show's ninth season. Luckily for the U.S.'s Cowell devotees, Simon will take his popular British talent show The X Factor Stateside in 2011. But with the loss of Cowell and fellow judges Ellen DeGeneres and Kara DioGuardi, Idol is looking ripe for reinvention. Season 10 starts Jan. 19 with new judges Steven Tyler and Jennifer Lopez joining Randy Jackson.