i also have an xbox 360, and i have finished modern warfare 2, and started playing odst, and cod mod 2 is awesome groundbreaking stuff with heaps of detail and is a definite must if you like first person shooters. Assassins creed 2 is way more detailed than the first one with heaps more interactive things and more ways to assassinate, and if you like rpg's is also a very good choice. where as odst seems like an expansion to halo 3, not much has been added and its rather short. also ur some lame drop ship trooped not the all mightyy masterchief. in short it seems like a way to make money by slapping the halo name on it, but is still a good way to pass the time