Simon’s Leaving Idol!

Not really.

Back in 2003, when American Idol was still finding its voice, Simon Cowell wrote a surprisingly substantive book named after his oft-repeated disclaimer, I Don’t Mean to Be Rude, But …. In the first chapter, he let readers in on the secret of true star quality: the X Factor, “indefinable” and “vital to anyone who aspires to stardom.” The X Factor might be vague and elusive (and also the name of a coagulating enzyme in human blood), but it is unquestionably powerful. It’s the name of the unstoppable U.K. show Cowell developed as a replacement for Pop Idol when a second season for that show on ITV had yielded underwhelming results. And it’s why Simon is leaving American Idol.

In a week filled with network scheduling drama, it’s more apparent than ever that in television, timing is everything. The tiniest details—a half-hour shift—can make or break a franchise. But Simon Cowell always knows what time it is, and it’s not so surprising that he will leave Idol (in the lurch) before its milestone 10th season to develop a stateside version of his U.K. hit. I hate the phrase “jumping the shark,” but last season’s addition of Kara DioGuardi was surely the first major sign of impending show apocalypse. (Is it a coincidence that her arrival made the number of judges four?) In a format in which the majority of the cast changes weekly, the stability of the judging panel is an anchor for viewers, and DioGuardi superfluously rounded out the 2009 cast like a suddenly adopted Leonardo DiCaprio. Paula’s departure was sounded this summer with a Twitter of doom—though I do admit I’m looking forward to seeing what Ellen brings to the judging table—and now Cowell’s decision, I think, seventh-seals the deal.

Of course, the character of the show cannot and will not be the same without him. For the past 8 years Simon has not only given out Idol judgment but taught America to judge; he’s the public face of the music industry and the template for millions of budding armchair critics. Forty-two Simon clones judging 42 Idol clones around the world could not accomplish precisely what he has here, with his tell-it-to-you-straight British authority and disingenuous disavowals of rudeness. He’s inimitable, irreplaceable—he has that certain something, that indescribable … what do you call it, again? Oh, yes, that X Factor.

But even if (when) American Idol goes gently into the Tuesday and Wednesday nights of history, things may feel less different than we expect. The X Factor, set to debut in Fall 2011, is still a singing competition, still on FOX. Viewers will still be voting. Simon Cowell will still be a judge. Paula may even be a judge. (She was a guest on the U.K. version in 2006, so she already knows the ropes.) Heck, why don’t we just bring Randy and Ryan over, too? And Simon is still looking for the same thing, that mysterious star quality he sought in his idols.

For now, we can only wait to see whether Seasons 9 and 10 will take American Idol out with a bang—or with the whimper we’ll undoubtedly hear umpteen times starting at 8 p.m., as Simon makes tonight’s auditionees cry.