It's all relative. And as snickerdoodle kind of said, retention isn't really related to overall population. If there are 50,000 players that continue to come back day after day, then that is more player retention than having 500,000 and then 200,000 one month later. Even going deeper than that, the REQ system encourages prolonged play, as well as the monthly updates which give us game modes and maps. Retention is on a continuum, so try not to use the initial drop in population as grounds for dismissing 343's point, as it's irrelevant when looking at retention on a grand scale.