QUOTE(used2bcow @ Oct 11 2011, 12:52 PM)
Sounds like a medieval Rainbow Six/Ghost Recon("the all original ones, not the dumbed down iterations

").
The way u described, seems like exploration, harks the days of Ultima, when all quests are written down on pencil and paper and time spent looking for the correct npc to invoke quests and such. Very nice.
Funny you mentioned that, I was actually comparing this with ultima 4 the other day (but no one knew what i was talking about) where you quest to become the avatar.. i think there's an analogy here where your humanity is somehow something you want to keep - although that's not clearly explained. The mobs in ultima aren't as cruel though
The open world as i understand is a bit metrovania - where the more you explore and do, the more zones you unlock but like i mentioned earlier, you can still go to places you're not supposed to and for me that's a brilliant design choice.
You can play as a single player but as long as you're online, you are also effected by the online choices that other players make in the form of clues and bloodstains from people who have died there. You can co-op but you can't co-op with your friends (unless you randomly find him) and you can pvp online.
Also, if you accidentally kill an npc - they remain dead in the game. And you can't cheat the system as the game is constantly autosaving.