Bungie's announcement on the (supposedly) $500 million game people were playing by standing in front of a cave and shooting:
The social experience of a cave farming run is amazing: the herding to get a team of Guardians all behind the line and firing in the right direction, the rush to grab the loot, the scramble when the panic wave starts, the beckoning glow from inside the cave. The speed at which the community organized around this activity was inspiring and humbling to us.
But shooting at a black hole for hours on end isn't our dream for how Destiny is played. Our hope is that social engagement in public spaces is only one part of the Destiny experience. Expect changes soon which decrease the efficiency of cave farming and correspondingly increase engram drops from completing activities.