in my opinion i dont believe that this is the true prequel it was made out to be. i think that this map may not entirely connect to the storyline, and that the cutscene is the real prequel. i think origins was the only map made in this "game" between Eddie and Samatha, and that the alarm at the end signifies some sort of attack. (zombies possibly?) anyways i believe that the other maps did in fact happen later on and werent made up by the two kids. regardless, i am interested to see how treyarch is going to continue zombies in the future. will they play origins off as just a made up map? are all the maps made up? another interesting thought i had was that in the next game we could pick up an entierly new storyline, perhaps of Samantha, Eddie, Maxis and someone else. this could start the "real" story assuming they go with the idea that all the others maps are made up. i guess we will just have to wait and see what lies ahead.
