I know the firefight mode has 4 player co-op but does anyone know if you can do co-op through out the campaign or not?
You're just clones of player 1, like Halo 1 and 2. I guess its not so bad in ODST because there were many ODSTs, you're even part of a squad of them in the game. In Halo you were the "last spartan" or the "one and only" Arbiter but then you play in co-op and there's another one of you... In ODST we get to fight along side other ODSTs anyway so having players 2, 3 and 4 as copies doesn't look ridiculous.
Yeah, thats true. I used to think that it would mess up the storyline because you are suppost to be "alone", but you are right.