Oprah Winfrey and Jessica Chastain are among those taking to social media to send off the host of The Late Show

Credit: Jeffrey R. Staab/CBS/Getty

After nearly 22 years as the host of CBS’s Late Show, David Letterman has chatted up mostly everyone. Now the attention he’s paid to stars of stage, screen and song is being returned to him in a big way.

Just this past week, some of his most famous buddies – including Bill Murray, Tom Hanks, Julia Roberts, George Clooney and Eddie Vedder – have stopped by to say goodbye to the late-night legend.

More overwhelming, though, are the number of former guests (Letterman has, after all, clocked more than 6,000 broadcasts in his 33 years as a late-night host) who have taken to social media to say their goodbyes.

Below, highlights from the tributes Letterman’s legend and how his retirement signals the end of a late-night TV era.

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After quite the social-media send-off, Letterman makes his final appearance on CBS’s Late Show Wednesday at 11:35 p.m. ET.