Adam Lambert and Kris Allen will be getting all the attention on Tuesday when they sing for the “American Idol” title. But new judge Kara DioGuardi will also be sharing the limelight.

Songwriter DioGuardi, who has worked in the past with Kelly Clarkson and co-wrote Ashlee Simpson’s hit single “Pieces of Me”,  is credited as co-writer of “No Boundaries”  — the new song that will be released as a single by the winner of the TV talent show, music industry sources say.

“No Boundaries” will get its first airing on Tuesday’s show in (presumably very different)  versions by Adam and Kris.  Web site Popeater.com will premiere the winning “Idol”’s recording of the song at 10 pm PT on Wednesday — moments after the 2009 “Idol” is crowned in the West Coast broadcast of the show on Fox.

Host Ryan Seacrest has revealed that Adam and Kris will also sing two other songs each on Tuesday — one must be a number they have done before on the show;  the other is a song chosen by “American Idol” creator Simon Fuller (Fuller is also the man behind British girl group “The Spice Girls”).

Among confirmed stars performing on Wednesday night as America waits to find out who they chose as their 2009 “Idol” are David Cook, Carrie Underwood, Queen Latifah, Black  Eyed Peas, Lionel Richie, Keith Urban  and actor Steve Martin — on his banjo?.

Rumors are flying fast about a host of other possible perfomers. Take your pick from Michael Jackson, David Bowie and Kiss — and maybe even ”Bikini Girl??”.

“Idol” producers aren’t saying — but who would you like to see singing a duet with Adam or Kris? And which of their own songs should they pick to clinch the title?