Jimmy Fallon Photo: IC

 Jimmy Fallon took the reins of the long-running Tonight Show on Monday night, bringing NBC's late night talk show flagship back to Manhattan after an absence of more than 40 years.

Surprise appearances, including Tina Fey, Joan Rivers, former New York mayor Rudolph Giuliani, Sarah Jessica Parker, Joe Namath and Steve Colbert, were among highlights of Fallon's Tonight Show debut, following the departure this month of long-serving host Jay Leno.

Actor Will Smith and band U2 were Fallon's first official guests as the show made its anticipated return to Manhattan's Rockefeller Center.

This marks NBC's second attempt to imbue the competitive late-night landscape on US TV with a more youthful vibe by appealing to the coveted 18-to-34 year-old demographic.

"I'm Jimmy Fallon and I'll be your host - for now," Fallon told the audience in the new studio where such beloved Tonight veterans Johnny Carson and Jack Paar once presided.

It was one of a handful of references to the show's recent troubled history. Jay Leno was initially replaced by Conan O'Brien in 2009, but returned months later in what was a public relations debacle for the network.