well, I don't like to sound like a killjoy but won't multiplayer be separate from the single player campaign? It's not coop play, so...
My understanding was two multiplayer modes, coop pve and competitive pvp.
This is the same way that Defiance multiplayer shooter works, which I have been playing lately, you have your single player storyline, story and side quests, yet anyone in the same phased instance can join in on your in progress missions for coop play (or can phase out into mutual pvp), or group up for 4-man coops, and everyone got the rewards since loots spawns in each instance, no having to pass the loot bag. You just get a little help from your friends and initially it was done very well, though that made it so anyone can stand there and do nothing and get credit. Their 'fix' was tagging so now everyone is in it for themselves and not for getting the assist. Makes my sniper useless in coop because I cannot one shot one kill, I got yelled at for not waiting for others to play tag. So of course while I wait for that, I get taken out and nobody revives me anymore.
So I hope they leave it truly coop like Defiance originally was and leave the competition for lootz on the PVP servers.