'X Factor's' Simon Cowell Introduces Surprise Twist: 'We Made a Mistake'

X Factor Diamond White PR P

[Warning: Spoilers ahead if you haven't seen Wednesday's episode.]

Mere moments into Wednesday night's X Factor, Simon Cowell admitted that once more, the show made an error with one of its contestants.

PHOTOS: 'X Factor' Season 2: Meet the Contestants

"We believe we made a mistake with one act," said Cowell, bringing back memories of last year's early elimination of eventual winner Melanie Amaro.

With that, hosts Khloe Kardashian and Mario Lopez made the big reveal: Perky teen Diamond White returned to the X Factor stage as the mysterious 13th contestant with a performance of Whitney Houston's "I Have Nothing," from The Bodyguard.

Britney Spears, who called up White with the good news in a taped segment, seemed proud of White, saying she "channeled Whitney" with her performance. Fellow judge Demi Lovato said she was trying not to cry, while L.A. Reid noted her choice was ambitious.

PHOTOS: An 'American Idol' to 'X Factor' Timeline

Could the addition of White back in the roster be a boon to mentor Spears' Teens category? Was this the decision of Spears, who gave White the ax in a total shocker last week, or did Cowell make a case behind the scenes?

 What do you think, X Factor fans?

, because I wonder if he loves me or hates me,” says the season two finalist in an interview with THR. "]