Mariah Carey and Britney Spears Credit: Venturelli/; Desiree Navarro/

Britney Spears officially signed on to judge Season 2 of FOX's The X Factor Monday, beating out rumored replacements like Mariah Carey, Beyonce Knowles and Janet Jackson.

After the announcement was made, Extra asked Carey what she thought of Spears, 30, joining the reality show. "You think I focus on that stuff? Have we met?" the diva asked. "I love [Britney], honestly. I think she's a very nice person, but I don't care who's going on that show -- as long as it's not me."

Spears, meanwhile, is "so excited about this whole experience," the engaged pop star said Monday in New York City. "It's going to be so much fun and so different from anything I've ever done."

X Factor creator Simon Cowell, 52, previously explained why Carey was no longer in the running for the judging gig. "I adore her, love her," he said. "But you can't expect someone who has just had two kids and has a record career to make the kind of commitment we would need on this show."

Pop star Demi Lovato, 19, also joined The X Factor as a judge Monday. She and Spears have replaced Paula Abdul, 49, and Nicole Scherzinger, 33, who were fired in January.