According to the early numbers, 11.3 million people tuned in for JIMMY FALLON'S debut on "The Tonight Show" on Monday night. 


That's down slightly from the 14.6 million who watched JAY LENO'S last episode earlier this month . . . but it beat out CONAN O'BRIEN'S debut back in 2009, when he attracted 9.2 million viewers.


(Speaking of Jimmy, there's video of his first stand up gig online, when he was just 17 years old.  He does a bunch of impressions.)