Halo 3 ODST's Firefight Mode

When we all heard about ODST coming out, I was looking forward to the Firefight mode. It is where you and 3 other friends go up against waves of aliens. This like Gears of War 2's Horde Mode but a lot more fun and its Halo. You even got to choose the difficulty from easy to legendary and it always provided a challenge and it was fun. Halo Reach's firefight mode is exactly the same like this one but with new levels and that is also great too. Firefight mode was awesome.