Also just got to the point where Alberto is upset that his “River” went away with Bobby’s servers, which suggests that some piece of it was remotely hosted, which technologically maps to my expectations about what is possible with current tech levels, but forefronts the patronage question.

One thing that is not mentioned is the hardware required inside the headset and on the laptop (remember how the artist trails behind Hollis, laptop in hand?). The kind of immersion effect described would require head-position tracking, maybe through some kind of accelerometer (it is impossible using GPS alone). Things like that have been built as research prototypes already, so they are not too far ahead. For example, the VAMPIRE project (http://www.vampire-project.org/), had an accelerometer and a camera-assisted setup for head-tracking. More conventional AR systems, e.g. http://www.cc.gatech.edu/~thad/032_research.htm, use a head-set camera combination.

That said, leaving aside what Gibson described, the model data itself could easily be stored in the local WiFi router and with the rendering (conceivably) being done on the laptop, it seems quite reasonable to realize.