Multiplayer does work. My group and I have been playing for hours with no real technical issues.
The major grips would be the following:
no one else can do anything while someone is conversing anytime someone loads into a new zone, everyone does the relationship with the NPCs is hindered because they only see to gain points with the person talking to them so unless the same person talks to them, getting the relationship up is difficult.
Give it time... we've been playing 2/3 weeks. The bugs eventually rear their ugly heads...
Right now we're in chapter three, fighting guys it takes 10 full minutes to kill, crashing every time we try to go to certain places, and half the time my friend logs in all his items are gone and we have to respawn them with debugmode commands.
But yeah chapter 1 and 2 were a blast... problems were rare