"American Idol" judge Steven Tyler and "X Factor" judge Nicole Scherzinger put aside their shows' rivalry by performing together ... and sharing and on stage kiss ... at the iHeartRadio Music Festival in Las Vegas over the wwekend .
The 63-year-old rocker and the former Pussycat Doll locked lips after performing Tyler's new single "(it) Feeds So Good."
Fellow "Idol" judge Randy Jac kson played guitar for Tyler and Scherzinger's duet .
Tyler goes in for the kill at the 3:22 mark .
What will Simon Think ??? HeHe
