Jimmy Fallon, Jay Leno Come Out Swinging - in Song

It had to happen. Jay Leno and Jimmy Fallon, the former reportedly about to be replaced as Tonight show host by the latter, have come to blows. Blowing out their lungs in song, that is. In a terrific and remarkably good-natured spoof that is getting high-profile play - not bad for anybody's ratings - Fallon's Late Night show opened on Monday night with his getting a call from Leno, who had just wrapped up his Tonight show. "Hey, kid. How you holding up?" Leno, in L.A., asks Fallon, whose desk in his New York office is strewn with newspapers reporting the NBC late-night-host succession.