"You look right at home," Letterman told his guest. "Obviously I'm thrilled and honored to be taking over for you," Colbert said.
Colbert will officially take over as host after Letterman retires in 2015. Check out this photo of the two from Colbert's visit:
And check out highlights from Colbert's appearance below:
Late Show with David Letterman airs at 11:35/10:35c on CBS. Will you watch Colbert's appearance?
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