At 32 years Letterman is the longest running late-night host in US history, first with 1982 debut of Late Night with David Letterman on NBC followed by The Late Show with David Letterman on CBS in 1993.
In 2013 he surpassed Johnny Carson’s 31 year record.
No date has yet been set for his replacement, Stephen Colbert, though he will leave The Colbert Report on Comedy Central, next week.
There is speculation he will begin in September, more than three months between after Letterman’s departure with CBS tipped to announce interim plans soon.
Craig Ferguson who ends The Late Late Show on Dec. 19 will be followed by guest hosts before James Corden begins in March.
Source: NY Times