CBS News released a statement saying that he has been suspended from his job as the investigation continues.
Colleagues were dumbstruck by the charges against Halderman. "I really can't believe the charges against him. I don't understand the motivation," said one producer who had worked with Halderman in the past.
The producer described Halderman not only as a well paid producer but one who was a "top shelf producer, highly regarded by CBS." Halderman was routinely entrusted with top stories ranging from the 1998 Olympics in Nagano, Japan, to assignments for "48 Hours."
Birkitt told her alma mater Wake Forest University that she originally interned in the writers' department at "Late Show" in 1996, and after graduating in 1997 worked at "48 Hours." She later returned to the "Late Show."
In a subsequent interview with EW.com, Birkitt denied Letterman was the cranky persona he appears to be on TV. "He's the best boss I've ever had," she gushed.
Earlier this year, Letterman announced on his show his marriage to longtime girlfriend Regina Lasko, who he began dating in the 1980s. The pair have a son, Harry Joseph Letterman, whose impending arrival Letterman announced on his show in 2003.
He did not mention his wife specifically or any other details of these affairs during his Thursday taping.
According to a source close to Letterman, all the liaisons Halderman was allegedly going to reveal regarding Letterman occurred prior to his March 2009 marriage.
The comedian went on to thank the Special Prosecution Bureau of the Manhattan District Attorney's office for its assistance, which culminated in the Halderman's arrest early in the day Thursday.
CBS issued a statement late Thursday night regarding the investigation and Letterman's decision to speak out on his show: "Mr. Letterman addressed the issue during the show's broadcast last night, and we believe his comments speak for themselves."
Howard Kurtz, a media critic for The Washington Post, said Letterman handled the situation "reasonably well" but cautioned that late-night comedians have a "delicate" relationship with their audience, especially because they often point out the infidelities of others.
"Somebody's going to put together a tape with all the jokes Letterman has done about womanizing public figures," Kurtz told Robin Roberts on "Good Morning America." "So if he becomes a punchline himself, I don't think he will lose his job over this, but clearly it undermines his job as a performer."
This is not the first extortion plot alleged to have targeted Letterman. In 2005, Kelly Frank, who worked as a handyman on Letterman's Rocky Mountain ranch in Montana, was arrested for allegedly plotting to kidnap Letterman's then-16-month-old son, Harry. Frank pleaded not guilty but got 10 years in jail for overcharging Letterman.
At the time, the comedian took it all in stride.
"I don't think I'll ever get tired of seeing my house on television while I'm in my house watching television," Letterman said on a March 2005 show.
Letterman was a longtime bachelor after his first marriage ended in divorce in 1977.
He has had at least one relationship with a co-worker in the past. Merrill Markoe, a comedian and author who was his longtime writer, was his girlfriend in the 1980s.