"We delivered," Cowell said at Fox's Upfront presentation for advertisers on Monday. "This has taken a year to get where we got to today and I am thrilled to confirm the return of L.A. Reid, the addition of Demi Lovato and superstar Britney Spears."
Spears, 30, took the mic first. "It's going to be so much fun and so different from anything I've ever done," she said. "I'm ready to find the true star."
Lovato, 19, called it an "honor" to stand with Cowell, Spears and Reid. "I'm excited to represent my generation and I'm excited to find a winner."
"I'm thrilled that The Voice has decided to compete with us," Cowell added, referring to how the other reality singing show had only previously aired during midseason but recently announced it will return in the fall. "We are going to make this the best series ever made."
The X Factor will air Wednesdays and Thursdays at 8/7c on Fox. No premiere date has been announced.
What do you think of the new X Factor judges panel? Who should host the show?