Kings of Leon rocked Late Night With Jimmy Fallon last night with a performance of their new single,"Supersoaker." The Southern rockers brought the soulful song to life as singer Caleb Followill belted in his whiskey-soaked croon "I don't mind sentimental girls at times / Miss don't walk away" over big hooks and scruffy guitar jangle. The song is fromthe band's upcoming sixth LP,Mechanical Bull,due out September 24th.Kings of Leon are set to join the Flaming Lips tonight at the Rock for Oklahoma tornado benefit concert in Oklahoma City.