The description of the video clip states: "Jon Stewart gives Chris Matthews the worst interview of his life." He sure did. At the end of it, Matthews made a somewhat fake move to smack Stewart (his friend!) upside the head. See for yourself!
Edit: Per Yeas & Nays on Examiner.com--
On a side note: Matthews was overheard discussing his Tuesday appearance on "The Daily Show," which featured a heated exchange with host Jon Stewart. According to one source, Matthews was steadfast in his belief that the debate left Stewart crestfallen, and Matthews victorious.