David Letterman's departure marks end of an era

When David Letterman does his final Top 10 next week it will signal the end of the longest late-night hosting career in U.S. TV network history and the end of an era.

The 68-year-old whoseacerbic wit once made him a renegade in the late-night world announced last yearthat he was hanging up his hat after 22 years behind the Late Show desk.

• Top 10 questions about Letterman's beloved Top Ten
• David Letterman packing his show with stars as end nears

His retirement, which begins after his last show on May 20, turns the page on athree-decade career.

The late-night TV landscape was a verydifferent place in the 1970s when thegap-toothed comedian got his big break onThe Tonight Show with Johnny Carson.

When NBC'sLate Night wth David Lettermandebuted in1982,Letterman earned his reputation as the rebellious kid on the comedy blockwith hisabsurdist, cynical and pencil-throwing style of humour.

Sixteen Emmysand 30-odd years later, Letterman's shtick is showing some wear. When comediccontemporaryJay Leno announced he was throwing in the towel atThe Tonight Show after 22 years, Letterman knew it was time to call it quits.

• Jay Leno's Tonight Show exit ends late-night career

"If you look around at the other people [hosting late night] and look at me, it's almost like a pair of shoes you haven't worn in a hundred years,"Letterman told Rolling Stone magazine.

"I still enjoy what I'm doing," he said."But I think what I'm doing is not what you want at 11:30 anymore."

The new kings of late night, Jimmy Fallon and Jimmy Kimmel, have completely reinvented the late-night game, focusing more on creating viral videosthan on sit-down interviews or written jokes.

• Super Bowl: JimmyFallonin post-game lip sync battle
• JimmyFallongets flipped-turned upside down for Fresh Prince ofBel-Airspoof
• Jimmy Fallon goes back to school in Saved by the Bell spoof

But they owe the success of some of that reinventionto the pioneeringLetterman, who originated many of their bits, according to bestsellingNew York Times writerBill Carter, who penned two books on the topic:The Late ShiftandThe War for Late Night.

"Letterman did a lot of this stuff," Carter said in an interview withCBC. "Jimmy Fallon loves to do games with the guests ...Well, Letterman did stuff like that. He had them do elevator races in 30 Rock hallways. He interviewed guests in barber chairs instead of regular chairs."

Despite being the trailblazer in innovative interviews, Carter said Letterman lost his edge because he simply stopped performing.

"He was outplayed because he stopped playing," said Carter, who says Letterman didn't like leaving the studio to record remotes for the show.

Letterman's viral weakness

Even Letterman himself admits that he's not up to compete in world of YouTube dominance.

"I hear about things going viral, and I think, 'How do you do that?'" he told Rolling Stone."I think I'm the blockage in the plumbing."

Stephen Colbert, who takesover for Letterman on Sept. 8, will have to simultaneously fill the icon's shoes and bring new energy to the Late Show.

• Stephen Colbert to take over The Late Show from David Letterman

The 50-year-old, who is best known for Comedy Central'ssatirical news show The Colbert Report,will also have to play the YouTubegame, while finding his niche in a pretty full playground.

Competing with Colbert and theJimmys are NBC's Late Night with SethMeyers andCBS'sThe Late Late Show with JamesCorden.

Norm Sousa, who is the host of the only Canadian late-night comedy showToo Much Information,said the viral video phenomenon can't last.

"We are talking about seven or eight late night shows trying to have two to three viral videos a week," saidSousa, in an interview with CBC. "If you do the math, I just don't think it's sustainable."

Thecompetition has created what Sousa calls a "late-night renaissance," but the the comedic battle royale won't be televised, he said.

"It'll be interesting to see how it will all pan out," he said. "[But] I don't think that late-night comedy will survive on TV."

Instead, he said, internetstreaming services like Neflix and Huluwill inevitablyget the last laugh.