The Insider.com

It was just confirmed by Fox Entertainment President Kevin Reilly that Mariah Carey has officially signed on to be the newest American Idol judge!

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"I am so excited to be joining Idol," Mariah told reporters, via Reilly's cell phone, underscoring what a late night deal this was. "First of all, I wanted to be there today, I wish I could have been there myself to tell you, but this all just happened a little quickly. I can't wait to get started in a couple of months! I will see you in January!"

As for who the other judges will be, Reilly said with 100 percent certainty that Jennifer Lopez will not be back on the show, but added that Randy Jackson's deal is up in the air. But he did add that Randy was very instrumental in getting Mariah on board.