So here I am, re-watching the E3 presentation for F4 and I see a piece of concept art depicting two BoS soldiers in a vertibird, and I think what if there was a co-op feature where you and a friend could be those BoS soldier or some paladins completing missions for the Boston chapter (assuming it's still functioning). These could be new maps or stay within the same world, but certainly custom quests, developed by Bethesda. Maybe even include people's settlements in there if they want to upload them? Just an idea.

Nope, it's not possible to 'slap on' multiplayer suport of any kind with a DLC or patch. It has to be implemented DURING early game development. Those that do have a multiplayer DLC actually have everything there at release and they charge you for the DLC to add a menu option.

It's been long confirmed that the game is single player.

nope

Naa I'm good. Thanks though.

No multiplayer. No Co Op, ever.

And http://www.gamesas.com/topic/1512524-fallout-multiplayer-discussion-thread/

If there's any justice in the universe, Beth will never implement any kind of multiplayer to its games.

And I still don't get why people seem to think it's possible to add MP simply with a DLC...

Because they've been hoodwinked by games that do? When in reality the games have released with the multiplayer support, but it's been disabled until the DLC is purchased. Was it one of the Resident Evils had co-op that was added in a DLC and somebody dug into the files and found that all the DLC did was enable the option to co-op?

That definitely explains it.

just NO.

Geez y'all need to chill down a bit. I've always daydreamed about coop in Elder Scrolls/Fallout, even though the technical limitations make it pretty impossible. Why all the emphatic "NO"?

Doubt it's much to do with technical limitations. I look at fallout as a very "lonely" thing and would rather travel the wastes myself. I rarely bring a companion and wouldn't like the idea of another PC wandering around doing stuff while I'm there. I think a lot of people feel the same way