Remember the Legendary ending in Halo 3? That was obviously a cliffhanger. The announcement trailer just shows chief escaping the in amber clad as it heads towards that mysterious object that was seen in the legendary ending. I'm hoping for a marathon crossover. You will recall that in marathon the humans had a planet size station and the transporting technology seen in halo 1 mission 343 guilty spark. I don't think that's a coincidence. Of course with 343 industries taking over, maybe that crossover is less likely, but nonetheless it would be cool as hell.