This feels like a submarine article, so I'm going to go off on a tangent, and ask, "For how long will this be true?"

With evolving documents like wikipedia and Conflict-free Replicated Data Type (CRDTs) coming into favor, it feels like writing could be a cooperative and multi-player game. Most of the meetings I go to have an EtherPad open for all the participants to collaboratively take notes during the discussion. I'd assume that collaborative editing of documents will become more of the norm.

Like exercising, perhaps one could show up and write in a shared document so as not to let your fellow writer's down.