Speaking purely as a player, not a GameSpot employee; I was deeply confused as to what the Reapers were even doing on Earth. It's as if they were just too lazy to walk in the first two games. I played Arrival DLC and from what I remember, I stopped the Reapers with a giant asteroid. Fortunately, ME3 quickly gets back into what it does fantastically well which is interpersonal stories effected by each players ME3 decisions. Main plot be damned, I love this game.