Just spoke with Activision. They believe it's the maintenace for PS3 network. I tried my Son's PS3 though, and his is working fine. Could be related to a combination of things. Port forwarding is not the answer, since I have been running MW3 without it for some time. But it could be related to passwords settings that differ from the PS3 network and the Call of Duty (both of mines are different). Since it can't validate you on the network (PS3 being down), you receive the error server 3 is not available.
Activision is aware of the problem and is looking into it. Ghost Recon Future Soldier works fine though. Might as well get use to it until 11:00 PM tonigh.
