The New York Times reports that BP worked with Electronics Arts programmers to design the game's underlying power and pollution models, and that in the game, "relatively clean systems like wind farms, natural gas plants and solar farms are branded with the BP logo, while the dirty options like coal are not." In return, BP paid Electronic Arts an undisclosed amount of cash.
This is flat-out wrong. When someone buys a game, they expect entertainment, and in the case of SimCity, intellectual stimulation and even some education. They don't expect subliminal influence from a corporation looking to push a specific agenda.
There's nothing wrong with programmers wanting to build the most accurate model for the trade-offs between electricity generation and pollution. So it's a good idea to go to many sources for the information, including alternate energy advocates and conservation experts as well as oil companies. But to allow an energy company this kind of access and control to an underlying model is the wrong way to go.