Fresh off their appearance at Radio City with Conan O'Brien the other night, Vampire Weekend stopped by The Colbert Report last night, and they sat down for this very funny interview. If you pay really close attention, you'll notice that when they start arguing about the usefulness of the Oxford comma, both Ezra and Colbert drop all signs of schtick for a few seconds and clearly have very strong opinions on the matter. It's sweet, funny and kind of nerdy. See what I did there? After the jump, they perform "Holiday."