How big a paradigm shift are Big Games? From his post on the paper, Big Games and the Porous Border Between the Real and the Mediated, Nicolas Nova pulls this suggestive quote:
Even as high-resolution computer graphics make the simulated worlds inside our computers more realistic, the actual world outside our computers is behaving more and more like data.
Migrating virtual space from the screened real estate directly in front of you to the land beneath your feet strikes me as an important geography lesson. I'm not at all sure why yet.
Wikipedia: serious games