Mariah Carey and Nicki Minaj made their "American Idol" debut last night.

+ "American Idol" Season 12 is off to a contentious start. By the 10-minute mark, judges Mariah Carey and Nicki Minaj were already trading barbs. Later, eye-rolls, more quips, and the B-word was dropped. Oh, and there were 41 contestants who earned golden tickets to Hollywood. (MTV News)

+ Carrie Underwood has been added to the forthcoming Grammys performer bill, which includes previously announced artists fun., Rihanna, Taylor Swift, Mumford & Sons, and The Black Keys. The 55th Annual Grammy Awards air Feb. 10 on CBS. (MTV News)

+ Take a look at Rihanna's cover art for her next two singles, "Stay" and "Pour It Up." On "Stay," she's snuggling up on a guy's shoulder, and that guy looks like it might be Chris Brown... (Idolator)

+ Shakira and her soccer star fiancé, Girard Piqué, have gone topless in a photo... but it's for a good cause. Shakira bore her baby bump with Piqué for a UNICEF "virtual baby shower." Fans can purchase "inspired gift" donations to help underprivileged children. (E!)

+ Ed Sheeran is getting ready to tour with Taylor Swift, and he says he'll also be using that time to pen his sophomore album. "I've got around 26 songs for the next record, and I've got another nine months on the road to keep writing as well." #ambitiousmuch? (Billboard)

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