Does Betty White owe David Matthews a big "thanks"? He's the guy who started the FaceBook group that helped get the actress a gig hosting 'Saturday Night Live' this weekend.

But, as she told Jimmy Fallon on 'Late Night' (weeknights, 12:37AM ET on NBC), David will get a different response if they ever meet. "I have not met him. And when I do, I'm gonna kill him! ... I am scared to death [about doing the show]," said White.

"Are you going to do any sketches with Jay-Z?" asked Fallon. She had a quick-witted response. Oh, she'll be fine this Saturday.