All good things come to an end, even for talk show titan Larry King.

In an internal memo sent late Tuesday, CNN President Jonathan Klein informed staffers that the 76-year-old talk show host would announce his decision to descend his primetime throne on Tuesday night at the top of his show, "Larry King Live."

"I'm looking forward to a future, to what my next chapter will bring," King told viewers. "For now, it's time to hang up my suspenders.

King has conducted some 50,000 interviews during a 53-year broadcasting career.

He marked his 25th anniversary on CNN this month.

He also holds a Guinness Book of World Records citation for hosting the longest-running show on the same network in the same time slot.

Yet for all his accomplishments, speculation had been building in recent months about King's departure.

In May, King hit a 20-year low by averaging 725,000 viewers in the 9 p.m. hour, according to Nielsen.

Critics slammed King for his inability to connect with younger viewers, even when interviewing such huge musical stars as Lady Gaga.

King's marital problems also made headlines. In April of 2010, King and wife Shawn Southwick, 50, announced their plans to divorce. A month later, the couple reunited.

As Klein's memo stated, King's family issues were a contributing factor in his decision to leave CNN.

"He wants to take some time for himself and his family. So he will end his run with 'Larry King Live' on his own terms, sometime this fall," Klein wrote.

The writing, in many ways, was on the wall for King and CNN. And yet, "It takes you by surprise," says Michael Rechstaffen, an entertainment writer and movie critic for "The Hollywood Reporter.

King's leaves, CNN goes younger

Rechstaffen spoke with Canada AM's Beverly Thomson and Seamus O'Regan from Los Angeles on Tuesday.

"It's a unique show," says Rechstaffen.

From the first show, where he interviewed then-New York Gov. Mario Cuomo, King's hour on CNN was considered the golden time slot on the network.

Presidents, celebrities and newsmakers from all walks found their way to "Larry King Live."

King's down-to-earth interview style made any guest relatable to his audience.

Yet, "The show hit a 20-year-low last month," says Rechstaffen

"I have a feeling he might have been in a situation where you can't fire me, but I quit."

King's resignation is a sign of things to come at CNN.

Plagued by low ratings and stiff competition from other news outlets, the network is actively overhauling itself from top to bottom.

"They've been doing a makeover across the board," says Rechstaffen. "They're looking for a younger face at CNN all around."

Who will replace the King?

Names of King's possible successors have made headlines in recent months.

CBS News anchor Katie Couric has long been considered a potential successor. That talk has cooled lately. Reports suggest that Couric is reluctant to leave CBS for another network plagued by rating troubles.

CNN's Anderson Cooper is another possible candidate. "He'd make an easy slide into the job," says Rechstaffen.

"America's Got Talent" judge Piers Morgan is also rumoured to be a possible successor.

In fact, according to reports this morning from RadarOnline, the reality-show judge and former British tabloid editor is in talks with CNN to become a new prime-time host.

If true, Morgan could possibly replace King this fall, and make an appealing host for CNN's lucrative international audience.

A spokesperson for CNN said that the network will not comment.

The New York Post also reported that CNN may slot Morgan as the host of a panel show.

The move makes sense, and would likely attract a younger audience for the slumping network.

Morgan's career was loaded with controversy as editor of the News of the World and the Daily Mirror.