Im going to have to call bull**** on needing to change your mac to get on multiplayer...
I am having the same issue with the serves being down, went through the motions and changed mac and used a diff PSN ID, get the same error servers are unavailable.
Im pretty damn sure if you were ban it would say straight up YOU HAVE BEEN PERM BAN.
So dont go wasting your time changing your mac...
On a side not he took WAY too many steps in doing it :P
rex 421 > rex 3.55.3 enable all lv1 patches then use the mac changer (for those of you who want to see for yourself) that this mac changing method will not get you on to cod bo2 servers right now :P