It was the debut of Jimmy Fallon on The Tonight Show and he came out swinging.
Fallon opened the show with, "Welcome to The Tonight Show. This is the first to be broadcast from New York in over 40 years. I'm Jimmy Fallon and I'll be your host—for now!"
The crowd roared over Fallon's twerking routine with Will Smith, and everyone was dazzled when the legendary band U2 performed on the roof at 30 Rockefeller Center as the sun was setting.
Fallon's Tonight Show debut was a ratings bonanza with an estimated 10 million viewers! Of course, the fact that Letterman was in re-runs didn't hurt, and neither did The Tonight Show's lead-in from the Olympics.
Steve Battaglio from TV Guide told INSIDE EDITION, "It helped that he had the lead-in from the Olympics, but obviously there's great curiosity when you have a new host of The Tonight Show for the first time."
More than 300 students at Fallon's alma mater, The College of St. Rose in Upstate New York, gathered to watch him on a big screen. Fallon gave a shout-out to his parents in The Tonight Show audience.
And guess who showed up when he cracked this joke, "To my buddy who said I'd never host The Tonight Show, and you know who you are, you owe me a hundred bucks, buddy."
The crowd went wild as Robert De Niro, Tina Fey, Mariah Carey, Kim Kardashian, Lindsay Lohan, Sarah Jessica Parker, Mike Tyson and an outrageously dressed Lady Gaga were among those who paraded to Fallon's desk to pay up, culminating with Stephen Colbert, who paid up in pennies.
Joan Rivers also showed up to pay up. It was her first Tonight Show appearance since she was banished from the show nearly 30 years ago during the reign of Johnny Carson.
Battaglio said, "To see Joan Rivers out there was a big shock. It was not only a great gag, but it was also a nice gesture to show that this is a new era."
Watch More of Battaglio's Interview About Fallon
So, what did the critics think of his first Tonight Show?
The New York Post called it a "triumphant" debut, while the New York Daily News gave him three out of five stars, noting that Fallon was "visibly nervous." And the Los Angeles Times was especially critical, finding most of Fallon's debut to be "low-energy."
Battaglio said, "The real test is, are people going to like having him in their homes night after night, weeks from now?"