Earlier today, the long-rumored inclusion of a multiplayer co-op mode was confirmed by Bioware. Not much was known at the time, but the developer has taken to the forums and posted a few choice details about the controversial mode. Players will be able to "choose from a variety of classes and races, form an elite Special Forces squad, and combine their weapons, powers and abilities to devastating effect as they fight together to liberate key territories from enemy control." You can check out those details here, but of particular note is the "Galaxy at War" feature.

The Galaxy at War feature is a "new way for players to manage and experience the galactic war from multiple fronts." There's also something called a "Galactic Readiness" level, which is measured by Shepard's ability to use all of his resources to defeat the Reapers. The GR system can be affected by using the Galaxy At War feature, which is to say that engaging in the multiplayer mode will somehow impact the outcome of the single player campaign.

Personally I'm not sure I'm okay with the idea of the multiplayer affecting the single player at all, but I suppose I should give props to Bioware for finding a way to ensure that multiplayer is at least tried out.