The graphic shows how we can view gaming & virtual worlds on a continuum depending upon how flexible the model is and who creates it.  This merge is happening with Web 2.0 technologies as well.  Facebook has become a gaming platform in and of itself and how desires to allow gaming consoles to access it (link).

While this post raises more questions than it solves, the intent is to show that in the same way that connecting back end systems became commoditized resulting in COTS middleware…the Front Ends of how we interact with software are becoming commoditized in a way that allows us to more easily traverse amongst them, i.e., from one virtual world to another, from a social networking site to a VW or within a game that has become so free form as to feel more like a virtual world.  All of these developments are a slow morph toward and end state that no one has designed.  It’s simply the way that technology undergoes natural selection when the selective force is human usability.