"We are turning the heat up on Idol this year and are thrilled to welcome Kara to the judges' table," creator and executive producer Simon Fuller said. "She is a smart, sassy lady, and one of America's most successful songwriters.
"We know she will bring a new level of energy and excitement to the show."
Fellow executive producer Cécile Frot-Coutaz added that the series had intended from the outset to have a four-judge panel, as both its British predecessor Pop Idol and current counterpart X Factor do.
"We've seen from our international series that having a fourth judge creates a dynamic that benefits both the contestants and the viewers."
But not always the judges.
Producers tried once before to add a fourth judge to the Idol mix, hiring New York DJ Angie Martinez to join the second season of the show. She lasted just five days before quitting, after revealing she had never bothered to watch an episode before signing on.
Martinez issued a statement at the time saying it was "too uncomfortable for me to tell someone else to give up on their dream," and producers quickly reverted back to the three-judge panel.
For her part, DioGuardi said she's worried about being the "new kid on the block," warning her fellow judges to "kind of, like, go easy with me a little bit," but said she was nonetheless "just flattered that they asked me to join them."
And lest any haters try to pit her against fellow female judge Abdul, DioGuardi actually credits the onetime pop star with being "one of the first people to believe in" her—she cowrote a song with Abdul for Kylie Minogue when she was first starting out.
"I owe Paula a lot, yeah. I'm gonna give her a big fat kiss when I see her."
As for her other new colleagues, DioGuardi called Jackson, whom she has worked with in the studio, "the most jovial guy with the greatest energy...I'm a big fan of his."
And Cowell, she said, gave her a congratulatory phone call over the weekend. "He was very encouraging and cool and welcomed me...made me feel like I don't need to be so scared."
Since DioGuardi only just joined the panel, she will likely not make her Idol debut until slightly later in the season, having missed out on the majority of the open auditions, which kicked off in San Francisco July 17.
She joins the judges' table for the first time this week with the New York auditions.
(Originally published Aug. 25, 2008, at 7:20 a.m. PT.)