After days of speculation, Mariah Carey is officially on board as a new judge on American Idol.  Fox made the announcement Monday.

In a statement, Mariah says, "As a singer, songwriter and producer, it’s going to be fun and rewarding to help find new talent and give back with American Idol....I can't wait to channel my creative energy as a part of this show which is a massive global phenomenon."

Similarly, she tweeted immediately after the announcement, "It's gonna be so much fun working on @AmericanIdol. As a singer-songwriter, I'm excited to help find and nurture new talent."

Mariah also phoned into Fox’s Television Critics Association panel in California, saying she is excited to join the show.

She fills one of the slots on the Idol judges' panel vacated by Steven Tyler and Jennifer Lopez earlier this month.  It's also been rumored that Mariah's pal, Randy Jackson, will transition from judge to mentor next season.  Idol returns to the airwaves next January.

Incidentally, Mariah's husband, Nick Cannon, is also involved in a reality TV competition: he's the host of NBC's America’s Got Talent.