Check out this video showing off Halo 3: ODST from Joystiq. Nathan Fillion's character Buck does the primary voiceover work, talking about his team, which has his Firefly co-stars Adam Baldwin and Alan Tudyk as Dutch and Mickey.  There's some hot toaster action with Tricia Helfer from Battlestar Galactica as well as Dare.  Oh, and some silly game footage along with the nerdery.

Take a look.