I just finished reading the first chapter of Ian Bogost's Unit Operations: An Approach to Videogame Criticism, and I'm really enjoying it.
Bogost's approach hinges on the concept of the "unit operation," a "mode of meaning-making that [privileges] discrete, disconnected actions over deterministic, progressive systems," and the first twenty pages of the book pretty much constitute an attempt to clarify this distinction.
I'll confess that he isn't a hundred percent successful. At the end of my first pass through the chapter, I feel like I might have a tentative grip on what distinguishes a "unit operation"-based analysis from "systems operation"-based analysis, but I strongly doubt that I'd be able to do something like summarize the difference between the two. I can't entirely blame Bogost for this: "units" and "systems" are both high-level abstractions; we're not exactly talking about apples and oranges here.
Determined to make it clear, Bogost starts pulling in conceptual machinery from a variety of different disciplines: half the fun of the book so far is watching the interesting thinkers pile up on top of one another. By page twenty we've moved through quite the array: Heidegger, Spinoza, Leibniz, Alain Badiou, "object-oriented" philosopher Graham Harman, "autopoetic systems theorists" Francisco Valera and Humberto Maturana, sociologist Niklas Luhmann, mathematician Georg Cantor, digital media theorists Janet Murray and Espen Aarseth, and poet T. S. Eliotall this en route to, of all things, a unit-operations-oriented analysis of Spielberg's film The Terminal (2004), in which Bogost concludes that the film is about "specific modes of uncorroborated waiting."
So, in conclusion, I'm not really sure yet exactly what Bogost is even talking about, and yet I've jammed the first chapter full of about a pound of bronze (in the form of Levenger Page Points). Being disoriented by brilliance is a good thing.