I am for multiplayer completely. If you don't like it then don't use it, simple as that...
Really the only valid point the Anti-MP guys (gals) have is that it would cost resources. This is understandable. While most of you say, "Oh it would be a waste of resources!" if done wrong then yea it would be. However if they did it right then, no it wouldn't. It would be quite the opposite. I'm not sure why everyone automatically assumes right off the bat MP (local/online 2-4 player co-op mind you) would be executed terribly and would just turn out like Fable II. (Even though I did like the co-op cause it allowed me to play with my friends and share the story together) Does no one think Beth is capable of doing MP correctly? I think they'd do and fine job.
Now some of you just wonder how they'd do it.... (well this would be my ideal way)
So basically (if I'm on console) I'd throw my friend an invite and then a lil notice would pop up saying
Dying.... if you die they can add a bleedout system perhaps? Like if Dragon Slayer dies he falls to the ground in pain and from here you kinda have to fend off the attackers untill there gone. If Dragon Slayer has some potions he can get back up, if not he'd have to wait for you to revive him. If you both die you just respawn at the nearest inn cause some guy saw you both out there and deicded to save you (idk think Farcry 2)
Interaction with NPC's shouldn't be too difficult now that time doesn't freeze when you talk to them so yea. Also resting/sleeping should go something like so. You press the rest button and then a prompt will appear on Slayer's screen saying "Sushi2k wants to rest for X hours. Continue?" and yea there you go. Yes theres friendly fire so you guys can just eat at each other but you can't loot each other. You can go to the Arena and perhaps have staked matches like Sushi bets his Ebony Longsword and Slayer bets his Necromancer Hood and whoever wins gets em. Any progress made in the game (such as MQ or Guild Questlines etc.) will not affect player 2 if they have already completed em. But if they haven't then yes they can still make progress though the questline.
After 9 hours of playing Slayer decides to go to bed for the night all he does is quit and thats pretty much it.
Since Skyrim has already announced no MP apparently I'd like to see either a RDR free roam or a Arena PvP in a DLC much like what RE5 or Dead Space 2 did. That way it won't take up space on the disk for you Single Player peoples.
Honestly I really would hope they would have at least considered a Co-op of some sort. Because only thing it'd do would add 100s of more hours of me playing that game on top of the 100s I already put into it and I'm sure many others. Don't get me wrong I loved MW and OB and played both of those games religiously. But I would have loved to have some online interaction with my friends rather than "Sushi stop playing OB and come play Halo with us!" All my friends love TES series and would love if we could all interact with each other on it and maybe do some dungeons or even PvP it out. But alas no such feature is added so we must go play our freaking CoD and other heavy multiplayer games.
TL;TR?
Make a PvP Arena or RDR Free Roam mode in DLC for like 10 bucks and we'd all be happy.