David Letterman had some fun Wednesday evening with the announcement that Jimmy Fallon will be replacing Jay Leno on NBC's Tonight Show.

The Late Show host began his opening monologue with a series of jokes about the issue including, "I happen to know Jay's got another job on a network that has greater viewership, higher ratings - Univision. He's going there."

Letterman began his monologue asking, "How many folks earlier today saw the white smoke coming out of the chimney at NBC? Anybody see that?"

After the laughter died down, he said, "I got a call from my mom today. She says, ‘Well, David, I see you didn't get the Tonight Show again.’ What are you gonna do, Mom?"

"It seems like we just went through this?" Lettterman continued. "Didn't we just go through this? Jay Leno now is being replaced – and this is the second time this has happened. I mean, crazy - he's being replaced by a younger, late night talk show host. What could possibly go wrong? Honestly. They’ve had pretty good luck with this in the past."

"But NBC, God bless them, announced the official date for Jay Leno's departure," Letterman added. "No mention of his official date of return, however, so. Don't know when that’ll take place."

And finally, "I happen to know Jay's got another job on a network that has greater viewership, higher ratings - Univision. He's going there."

This was obviously a joke about how during February's sweeps week, NBC actually came in fifth behind the other big three networks and Univision.