Ending months of rather wild speculation, Ryan Seacrest announced yesterday that Jennifer Lopez and Steven Tyler would be joining Randy Jackson at the "American Idol" judging table for the show's tenth season. Everyone from Howard Stern to Betty White had been rumored as possible replacements for outgoing judges Simon Cowell, Ellen DeGeneres, and Kara DioGuardi, and the choice of Lopez and Tyler, though clearly more sensible than such wild cards, has TV critics questioning the producers' wisdom:

Lopez and Tyler were hired for the wrong reasons: The hiring of big-name musicians suggests that the producers "took the wrong lesson from the failed Ellen DeGeneres experiment," says James Poniewozik in Time. DeGeneres did not lack credibility as a judge because she wasn't a musical artist, but because "she wasn't willing to judge." The show should be looking for "a good TV judge first, and a good musician second... J-Lo and Tyler could be both—I hope so. But if Idol has gotten those priorities reversed, this pick might hit all the wrong notes."
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And neither can fill the gaping void left by Cowell: "The show needs Simon — or some version of him," says Alan Sepinwall at Hit Fix. "It doesn't need an aging rock star [Tyler] whose decades of success won't mean much to the tween 'Idol' power-voters." Cowell and his caustic British wit were essential, and neither Lopez nor Tyler can bring the same mean wisdom without inciting hatred from fans. "Simon got away with it because he was grandfathered in from the start; we had years of history of him usually being right."
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Lopez and Tyler aren't the most important new hires: There's a new arrival "hellbent on knocking the cobwebs out of this semi-stale franchise," says Lisa de Moraes in The Washington Post, but it's not one of the new judges. Rather, it's Jimmy Ionvine, Interscope Geffen A&M Records Chairman, who's been picked as the show's permanent in-house mentor for the new season. Fans should "expect a laser focus on Iovine as he works closely with each aspiring singer to mold them into a marketable, moneymaking commodity."
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