Dragon's Dogma or Borderlands 2. I'm not sure.
I didn't really play a lot of this years releases. Aside from Dota 2 (1000+) I played Ratchet/Jak collection probably 20 hours, must have played 30+ hours of Kingdoms of Amalur, maybe 15 hours of Starhawk, and a few hours of Torchlight II. Mostly I've been playing last year's releases like Saint's Row and Deus Ex.
hmmm... strangely enough, I think it was probably Kingdoms of Amalur: Reckoning, which I played around 95 hours of including the two DLC packs. I also played a ton of Skyrim early in the year, but probably not more than half of the 140 total hours I've put into it.
Pretty much the same here, except I played all of my Skyrim this year. Sorry, 2012 releases. Other than those 2 and some forty hours in Dragon's Dogma, I've mostly been playing shorter games from the previous years, like Batman and Portal 2.
Final Fantasy 13-2 and Persona 4 Arena both felt like they took forever, I also probably played about as much Tekken Tag 2 as either of those games. If we're counting non-2012 games it was Chrono Cross, because I needed to beat it a couple times to write a blog I wanted to do, and never got around to it because of NaNoWriMo, then finals, and now GOTY.
Probably Mass Effect 3 or Diablo 3 with Halo rapidly catching up. Played a ton of FTL too.
Just checked Raptr and I somehow put 38 hours into Spelunky and still have less than half of the achievements. And another 38 into the Binding of Isaac, which I already played the crap out of last year.
Defintely Guild Wars 2. Albeit I'm slowly starting to resent the heavy dependence on RNG and grind for earning a legendary. I never should have commited to getting one.
Though I'm quite impressed by the steady flow of fresh content and events for it. Oddly enough sPvP and WvW haven't really caught on with me yet.
Either Mass Effect 3 or Trials Evolution. I think I have 4 days of playing time on Trials, so at least 96 hours, and I don't know if that includes time in multiplayer. I've played the campaign in ME3 nearly 3 times, so that's a good chunk of time, plus I've been way into the multiplayer lately. I've spent at least another 15 to 20 hours on that.
Persona 4 Golden is catching up quickly though. I don't think it will surpass those two this year, but I'm sure it will before long.
These are the only ones I can think of since they all have at least triple digits next to the hour mark.
Skyrim (multiple playthroughs because mods mods mods)
Guild Wars 2
Dungeon Fighter Online.
Not a surprise that most of the games on that list are online multiplayer ones.
So, I just checked my Steam, and to my surprise it was Super Monday Night Combat with 272.1 hours. Damn, I really love that game.
Second was XCOM: Enemy Unknown with 132.8. Put it down after I finally beat an Iron Man game on Classic difficulty.
Third was Crusader Kings 2 with 88.6. Would have been much much more if my computer didn't die in the middle of a session. Built a new rig but haven't gotten back to it yet.
And then I suppose fourth would be Xenoblade Chronicles with probably around 80 hours or so. That game was amazing, and I want to play it again sometime.
This thread has really interested me to see how much time other people have spent on specific games. I'm only half suprised to see that Mass Effect 3 was a popular choice. The multiplayer was pretty fun, and with all of the free updates, I have been considering diving back into it.
I normally burn out on a game right around 60 hours or so. Skyrim last year, the Fallout games, Borderlands, etc. Diablo 3 this year though I have about 125 hours in. I just jumped back in a few weeks ago, still haven't beat Inferno... I should get back to that.