A very brief segment of Halo 4 footage was shown on Conan O'Brien today; check it out through the break. Unless you're Australian, of course.
According to both Joystiq and Kotaku, the video posted below contains about ten seconds of Halo 4 in between a no doubt hilarious skit about the game.
Both Conan O'Brian and Andy Richter have been confirmed as voice actors in the game, according to Microsoft's Joe Dimiero, so at least the duo weren't joking about that bit in the skit.
"More announcements on the rest of our voice cast [will be revealed]in the coming months, Dimiero told G4.