K, i just played 1 hour of this Yesterday on the Xbox Rent Place (It was in French >_<) Luckily, it had subtitles, what can i say is EPIC WIN
In my opinion, Halo 3 is a total stuff compared to this.
Also the story, the most impressive thing is how you get more and more involved in the story, finding your teammates helmets and looking a flashback from another perspective, also even playing it! (Yes, you play the flashbacks as another characters) Also i felt the graphics much better and detailed than Halo 3. I found it to be a good game.