Speaking to videogaming247 at the Sierra Spring Break 08 in Mallorca last week, Terminal Reality studio director John O'Keefe said that there will be no online co-op enabled in the main Ghostbusters campaign, but that the various side-missions will include this feature.
"If you remember, the comedy and scares were really important to the feel of the movie and we really wanted to replicate that," he said. "We want you to feel like you're a Ghostbuster...
More through the link.