by Breaking Celebrity News Staff

Things got a little testy between David Letterman and Paula Abdul in her Tuesday appearance on The Late Show to promote her new show, The X Factor.

Letterman bluntly told the sexy judge her new show "looks just like American Idol," to which Abdul replied, "It's so not!"

"How is it not?” Letterman said. “You have Simon, and you, and then a guy who looks exactly like Randy Jackson (He meant L.A. Reid) ... you go places -- you go to church basements and rotary clubs -- you get kids out, you get grownups out dancing, singing ... you get ‘em to Hollywood and you have a weekly competition where the viewers gets to vote who will return.