According to BioWare community manager Eduardo Vasconcellos, Sony has not yet approved the promotion to run on the PlayStation 3. He said BioWare and Sony are presently working to hammer out a compromise, but none has yet been reached.
BioWare did not say why Sony is blocking Multiplayer Challenges from Mass Effect 3, and as of press time, the publisher had not responded to GameSpot's request for comment.
Mass Effect 3 Multiplayer Challenges are promotional weekend events that have been running since launch for the Xbox 360 and PC versions of the game. For example, this weekend, BioWare is offering all participating squads in its Operation Resurgence challenge +10 percent additional experience to encourage players to try out the game's new maps.
For more on Mass Effect 3, check out GameSpot's review.