If you pre-ordered Wolfenstein: The New Order, you might be able to play Doom multiplayer sooner than you think.
Id is still holding the planned, exclusive MP beta closer to Doom's launch next spring, but the developers holding an extra alpha test "relatively soon," and they're drawing random names from that beta group to fill the slots.
Register yourself for the beta using the instructions you received with Wolfenstein, and you may just be chosen.
Developing...