One of the most interesting aspects of the new SimCity is the way pollution and the environment will play into the new multiplayer features. The latest installment of the franchise is set to launch sometime in 2013, so there's no playable version yet for me to see the mechanic in action; however, EA Maxis was willing to play out some scenarios during a visit to the Emeryville, CA, offices last week.

Once a new game is started, players can create a region and invite friends to add their own cities. Each city has the potential to share with its neighbors -- the citizens of one city may travel to the other to enjoy casinos or shopping, for example. Keeping Sims within the city happy keeps the economy flowing.

Connecting cities in this way opens the door to interesting scenarios: one city could be a supplier of coal to other locations, reaping the cash rewards of being a supplier and allowing its neighbors to progress in the game despite limitations. It encourages cooperation, something EA Maxis will support with added bonuses and possible achievements when SimCity launches in 2013.