What happened to other post-structural forms?
Well you're talking about a gaggle of curiousities; YouTube storytelling, fan fiction, audience participatory theatre, techno remix culture, a lot of things that are really driving at interactivity, in my opinion. Games are, I think, a purely post-structural form, because they provide interactivity.
I was taught how to design games is that there really isn't anything except the player's experience.
I was taught game design largely by three more experienced people I worked for/with. One was Chris Crawford, and he gave me the impression that interactivity had a discrete structure (like the "conversational metaphor" he uses for it) based on verbs, and that structure was ultimately the representation. You can get an indication of this in the Storytron engine, the way human relationships are defined precisely by floats and how the story is rigged up by Fate, which is like a passive difficulty adjustment system, but for storytelling instead of challenge. Another was Chris Bateman, and he taught me about different types of play and how the audience was quite diverse in its relationship to those four types, and in Play With Fire (being released on Manifesto very soon) you can see that in the design: players are given a Fun, Challenge and Puzzle path, and they can take the content at pace depending on what they like. Craig Perko, whom I'd researched with on an experimental drama engine last summer, and have been making a casual game with since the fall (you know how economics works) has taught me something rather in the middle, as a result of many arguments with a variety of people in the comments of blog posts. His idea is that game rules, the structure, is like a social entity that the player is engaging with, at least, it can also be a referee for other social entities. His view is, to my mind, really a conceptual breakthrough, because it gets well over the dichotomy of 20th century analysis and gives a paradigm for strong game design, it aknowledges structure as a means to engage the audience in a very post-structural way.
You can get a concise view of the spine of Game-Design-As-I-Know-It by reading Chris Crawford On Interactive Storytelling, 21st Century Game Design (Bateman) and this recently published mini-essay: http://projectperko.blogspot.com/2006/1 ... -play.html
The bottom line: it seems like a truism that the player experience is the most important thing, and even moreso to a generation of producers that were raised on games, we're like the Martin Scorsese generation of game makers; but mechanics, the structure, is the fundamental fulcrum to supporting a play experience, forget that at great risk.
Tying it back to Jenova's thesis, flOw gets it right, because its experience is well integrated into the workings of its mechanics; it lets players find their own pace by-verb rather than through the variable adjustments of a tacked-on, buerocratic system.