Lady Gaga, Will Smith and several other stars join Fallon at his new gig. Take a look.

Jimmy Fallon's excellent start at "The Tonight Show" is going to push everyone in late night to work harder, and viewers will be the winners.

You could see that Monday night. On "The Colbert Report," Stephen Colbert delivered classic comedy skewering Bill O'Reilly's self-congratulatory take on Bill O'Reilly's interview with Barack Obama.

On "Late Show With David Letterman," Kevin Spacey delivered wonderful impressions of Bill Clinton and Johnny Carson. The cast of "How I Met Your Mother" presented a Top Ten list about surprises in the CBS sitcom's series finale. Josh Radnor had the best joke: "Someone finally points out that I don't sound like Bob Saget."

But Fallon delivered the goods in the premiere that aired midnight. He had a huge boost from the Olympic lead-in and the gold-medal victory of U.S. ice dancers Meryl Davis and Charlie White. 

Fallon danced with Will Smith. U2 performed atop 30 Rock in a gorgeous sequence. Later the band helped its Oscar chances with a poignant performance of "Ordinary Love." Will the U2 performance at the March 2 Oscars be that good?

The "Tonight Show" gained a lot of attention for a parade of celebrity friends who bet Fallon that he would never host the NBC late-night institution. The celebrities paying off $100 bets included Robert De Niro, Tina Fey, Joan Rivers, Lindsay Lohan, Mariah Carey, Mike Tyson, Lady Gaga, Sarah Jessica Parker and Joe Namath. Colbert showered Fallon with change, and former Mayor Rudolph Giuliani thanked Fallon for bringing "The Tonight Show" back to New York.  

"I'll be your host for now," Fallon joked in his monologue.

But he's going to be around for a long time, because he has qualities that win viewers' loyalty. Will Smith got at Fallon's essence: "The people are coming because of your heart."

Fallon's emphasis on comedy in music will set him apart from Letterman and ABC's Jimmy Kimmel. So will Fallon's sweetness.

Fallon is going to cause viewers to take another look at late night, and that's good for television. Tuesday night Fallon has Jerry Seinfeld, Kristen Wiig and musical guest Gaga. Kimmel offers the premiere of the trailer for "Guardians of the Galaxy," the new Marvel movie. Letterman presents Olympic gold medalist Sage Kotsenburg and musical guest Cole Swindell.

Fallon has shaken up late night in a good way.