Heres my oppinions: I certainly would enjoy having Co-Operative gameplay as optional. There have been numerous ocasions when i've wanted to connect to my girlfriend's pc just to help her out on a certain part. However, as much as making it a MASSIVE multiplayer... Im not sure about that. They would have to change a lot of things. For example, supposing it was an MMORPG, the quests would be on first come, first serve basis, which wouldnt be good for newbies because most would be done. Second, Bethesda would probably try to charge by month (Which i refuse to do, thats why i dont play games like everquest or city of heroes). So finally, I would love if Oblivion was left like Morrowind, but with Co-Operative mode, where one could 'transport' his character into another player's 'Map´ (Keep in mind that even though its the same Map, just because you killed someone in your pc, shoudnt mean it is dead on someone else's pc) Edit: After serious consideration, i realized something: Even though you are "the incartane" on Morrowind, bethesda could allow us that WHEN we TRANSPORT to another Pc, we become regular characters, leaving the title to whoever you connected to. Example: I beat the game. Friend B just started the game and needs pointers on where to buy stuff. I connect to his pc, and appear to be a "regular citizen, level 100". Where as, if Friend B connected to me, I'd be the almighty, and he'd be the humble servant :P It could work, basically what we want is to transport ourselves into someplace else, keeping our stats, name and equipment, right? So it could be done! Heres another example I have for the Co Op idea. I start the game, Friend B wants to join, he'd then be 'born' as some random NPC. A file is created so that whenever Friend B rejoins, he would continie where he left off (even if he appears out of mid air, we can say he 'teleported')
