Let's say you bought a car that was not ready to be driven. Something that prevents you from interacting with other cars...let's say there were no headlights, or better yet no tires. Let's also say that you waiting a long time to buy this car, you had anticipated it, and you had been even excited about it. It is finally released, but not driveable. You are told that the problems will be worked out in the coming weeks, but for now, just ... wait, no you are not told anything.
Would that be acceptable?
Bottom line: They released an incomplete product. Give them time to get the servers up and running properly while they work out the kinks you say? If this company had never released an online multiplayer FPS game before, I could give them the benefit of the doubt...
The people waited a long to to get this game, it is incomplete, they should know how to do this all by now. Bottom line: people can complain all they want, but returning the game for a full refund is much more effective