Mottola, 60, is a music executive who is well-known for revitalizing Sony Music Entertainment. He co-owns Casablanca Records, a joint venture of the Universal Music Group. Mottola famously married and divorced Mariah Carey and is now with Mexican pop singer Thalia.
Mottola's high status in the cutthroat music industry means he's well-positioned to be the show's harsh voice of expertise. This is the tone that made Cowell so popular.
Recently, Idol has had a string of guest judges, including Victoria Beckham, Katy Perry, Mary J. Blige, Joe Jonas and Neil Patrick Harris. Some have speculated that the appearances were auditions for the stars.
The 9th season, Cowell's last, is also Ellen DeGeneres's first. She replaced Paula Adbul who left last year.