Simon Cowell confirms that he IS leaving "American Idol".

E!: Simon Cowell is leaving American Idol.
No, really. It's official now and everything.
Simon just told reporters at the TV Critics Assocation winter press tour:
"There's been a lot of speculation [about my future], partly because we didn't have an agreement. We reached an agreement formally about about half past 11 this morning. Where we have come to is that The X Factor will launch in America in 2011, with me judging the show and executive producing the show, and because of that, this will be my last season on American Idol this year."