It depends on the game. If the multiplayer is good then I can play for days. I almost never replay the single player anymore.

I love single player, nothing beats a great story

Online can extend a game's life, but all the best moments for me have always been single player.
Best if they're designed for single player, optional co-op usually means concessions have been made for both modes.

Only Journey has managed to enhance the experience for me through multiplayer interaction.
Second best would be Dark souls, yet at a distance already. The multiplayer and sometimes overload of spoiler messages was often breaking immersion.

Couch co-op is great for certain games, online not so much.

I think just about every game should have COOP multiplayer. Competitive multiplayer can go die somewhere. All it is is capture the flag or deathmatches 99% of the time with no creativity whatsoever.

No, I'm not.

I like single player more, but I do enjoy multiplayer whether it's co op or some competitive.

I don't really think multiplayer is phasing single player out though. Infamous Second Son is Sony's biggest upcoming title and it's already been commented on that there is no online multiplayer(though I do suspect we'll have user generated content.) EA is releasing Mirror's Edge 2 which is more than likely going to be a single player experience with some online multiplayer tacked on. Square Enix is releasing Final Fantasy 15 and Kingdom Hearts 3.

Just like last gen, there will be games that focus on single player, having single player and multiplayer, or games that focus on multiplayer.

1. Single player
2. Local multi player
3. Online multi player

If a game lacks 1 it is a massive hit for me, if it lacks 1 and 2 then I do not bother.

I'm only interested in single player modes, so I'm against the idea of multiplayer taking resources amd ideas away from it. Thankfully, that only happens in rare cases.

The problem, though, is that we're on a point where we don't know if the multiplayer modes are added because gamers want and demand it, or because devs decide to put it and make it an essential feature, leaving players with no other option than to play it. And there are cases of both types.

But of course, publishers will try to make multiplayer a priority. Not because it adds something to the game, but because it's easier and cheaper for them to release expansions for the multiplayer than to make it for the single player.

Most of my favorite games still have a very high rate of single player options.
Uncharted
Killzone
MGS
God Of War
RE

So I'm pretty ok as of now.

Not at all.

I actually dislike multiplayer on my games, unless its an MMO. I advocate that Single player games should do what they do best and stay single player games. Co-op modes and offline co-op should definitly stay around if devs want it.

But multiplayer modes on single player games are always inferior experiences compared to completely fleshed out worlds for the purpose like MMO's. If i wanted to play a shooter, i would sooner get Planetside 2, Destiny or Defiance than Halo or CoD. Those are just maps circling and doing the same thing. For me, that gets dull really fast.
The one i played online the most cause i wanted to get the best ending was mass effect 3 online multiplayer, and while it was co-op, it made the game look bad compared to the single player game.

In conclusion, multiplayer modes are a waste of time. Obviously, there are enough people that seem to find them worth playing though.