Since there isn't one of these yet, I figured I'd make one so people can pass along tips on achievements, talk about game play, etc.
I played my first co-op session last night with Mister Chief for about three hours. The majority of which was filled with me asking, "How did you get over there?"
To which Chief replied, "I jumped you ****ing idiot." (That took up about 2.5 hours of talking.)
This game is a great change of pace from Gears, which has consumed by 360 time for e the past months.