Speaking of SimCity, here's a summary of a talk by Will Wright on Designing User Interfaces for Simulation. Among other things, Wright addresses the question of exposing the simulation model, which often comes up in criticisms of the game (after the jump).
Some educators have asked Maxis to make SimCity expose more about the actual simulation itself, instead of hiding its inner workings from the user. They want to see how it works and what it depends on, so it is less of a game, and more educational. But what's really going on inside is not as realistic as they would want to believe: because of its nature as a game, and the constraint that it must run on low end home computers, it tries to fool people into thinking it's doing more than it really is, by taking advantage of the knowledge and expectations people already have about how a city is supposed to work. Implication is more efficient than simulation.
Other good tidbits in the summary cover how Wright had to compromise the extensibility and modularity of the code to make it runnable on a (relatively) slow home computer. Designing User Interfaces to Simulation Games [Don Hopkins]