With DiGRA ’13 coming up in 2 weeks, I went searching for an accessible version 
of my keynote at DiGRA ’05, for which the short piece “The Last Word on Ludology/Narratology,” which I posted a few weeks ago in text and slides, was just the preface. The text of the keynote itself, “Games as Joint Attentional Scenes” can be found on the Google Books site, since it was published as a chapter in Words in Play edited by Suzanne De Castell and Jennifer Jenson.
And here is a related journal article:
The central argument of both the conference talk and the journal article is that games precede language and arise from the powerful cognitive/cultural apparatus that underlies all human symbolic communication: our ability to point to something and to know that someone else is thinking about the same thing that we are thinking about. The pleasure of games is the pleasure of recognizing this joint attention and consciously synchronizing our behavior. Therefore, my standard reference point for What is a Game? is Ring Around Rosy, which rests on the simple pleasure of anticipating, orchestrating, enacting, and witnessing everyone- including oneself! – doing the same thing at the same time.
And taking games as the first medium, and the building block for the crucially humanizing medium of language, I extend the framework to include all media as the means for expanding and refining the experience of shared focused attention. I discuss this in the Preface (esp. pp 13-16) and Chapter 13 (esp. p. 380) of Inventing the Medium, and also in these related posts:
Janet H. Murray 