Just set Steam to show all games released by date and I'll do a quick blurb on everything from 2012 I played I happen to see. I actually looked at the list of 2012 games the other day and came to the conclusion my GotY was either Dark Souls or Crusader Kings 2 and I eventually decided on Dark Souls. Had higher peaks of funneninity.
Also after typing this up, holy shit I play a lot of garbage.
Planetside 2: Seemed like it would be fun if you had a solid band of bros to play with AND if you got cert points faster. As it is it seems like you have to grind the Bajesus out of it to get unlocks. On top of that there seem to be "This item, only better!" unlocks, not just sidegrades. Uninstalled after a couple hours.
Cargo Commander: Fun randomized platformer, slightly like Spelunky in space. Unfortunately not as sharply designed as Spelunky so it loses some attraction after a few hours unless you're competing against bros on leaderboards. Still a pretty good game.
Natural Selection 2: Excellent multiplayer FPS with some technical issues, which they admittedly have been working on. Also unfortunately slowly losing its playerbase, probably not enough to be completely dead but it's a shame it isn't holding on to players more. Deserves more players.
Conquest of Elysium 3: Probably isn't a 2012 game but it's a 2012 game on Steam so that counts right? Right. Good easy to learn turn based strategy, main drawback I've found is that it can be a royal pain in the ass dealing with neutral monsters stealing your buildings. May depend on map type but I've had absolute hell in my most recent game just moving armies around cleaning the same parts of the map over and over.
Hotline Miami: Seems fun when it works for 15 minutes, but it's buggy as absolute shit on Windows 8. The only game I've had issues with in Windows 8 actually. Assuming the developer fixes it it could be fun.
Dishonored: It's pretty alright. I thought the sneaking wasn't particularly well executed, the combat is laughably easy even on the hardest difficulty settings and with no combat spells/upgrades, and the story has a few dumb decisions in it. Still, the level design was mostly alright and I didn't have a BAD time.
Xcom Enemy Unknown: It's pretty good. The increased emphasis on dice rolls and a more boardgamey feel might put fans of the original off, but assuming you can roll with it it's mostly well designed. The lack of random maps and the goddamn scripted council missions are the biggest disappointments. One of my favorites of the year despite the disappointments.
Cortex Command: Not really finished despite the guy saying it is. It's playable but the AI is pretty horrible at it. Price is outrageous. Despite all this you can still have fun moments with silly shit happening but there's a lot of entirely justified anger in the Steam forum for the game.
Castle Crashers: Side-scrolling beat 'em up, pretty alright but older examples of the genre (Golden Axe, the D&D arcade games, those X-man and TMNT arcade games) are better at it. Castle Crashers' halfassed leveling system should've been dropped in favor of making it more arcade-like in my opinion, but assuming you like mashing buttons to beat lots of baddies up it's still pretty alright.
Torchlight 2: Like Torchlight, only a bit better! After getting through the game I can safely say it doesn't take my crown of greatest loot whoring action RPG, but it is pretty damn enjoyable and a good upgrade over the first. Well worth some money if you like clicking the treasure out of monsters.
Diablo 3: A non-Steam game, how horrifying. Might give an initial good impression as colors are exploding out of your monitor and loot is flying everywhere, but after a while you'll come to realize how piss poor the loot in Diablo 3 really is, how annoying the higher difficulties are, and how the skill system is unsatisfying in the end. If you find it for a freakishly low price and have a buddy to play it with you can have a decent time, but otherwise you're far better off with Torchlight 2.
Borderlands 2: Like Borderlands 1 only better in most ways. Better enemy AI (Marginally), enemies react to being shot more, more enemy variety, better skill trees for the classes, overall noticeably harder than the first game, etc etc. Biggest letdowns are inexplicably low loot drop rates compared to Borderlands 1, and the NPCs talk SO GODDAMN MUCH. For every amusing line you'll get buried under 10 lines of shit. If you can tune it out it's not much of a big deal but it does get annoying when all you want to do is shoot bandits for guns.
FTL: Disappointing in the long run. I like the combat system and ship management, but the game leans so heavily on constant combat encounters it gets tiring, and unlike most good roguelikes doesn't have as many systems for a knowledgeable player to get good items/avoid disaster. It may be I didn't play enough FTL (Despite dumping 16 hours in it) to learn any of these secrets, but the impression I got was it leans almost entirely on luck. If the game had significantly more content and seemed to be better designed I'd be more for it, but as it is I just like it and think it's ok.
Dark Souls: Extremely well designed, tons of secrets and layers to improve/change your gameplay as you learn them, interesting setting, great combat system with many MANY ways to handle things. I was extremely impressed by this despite the horrible PC port, hence saying it's GotY and RPGotY. It's an RPG because there are numbers you see.
Counter-Strike Global Offensive: Eh. Counter-Strike-like. Played the beta of it shortly before release. Seems like CS, I can't be assed to notice any major differences between it, CS:S, and HL1 CS. You'd need 1eyedprophet for that. It does have gungame built in which is nice.
Sleeping Dogs: Haven't finished it yet but it seems a bit light on content. That said the melee combat is pretty entertaining. Pretty alright game.
Orcs Must Die 2: It's like OMD1 only a bit better. The upgrade system is slightly grindy but lightyears away from the grinding in something like Dungeon Defenders. This is probably the best of the action tower defense games I've played.
Endless Space: Still poking at this and haven't entirely made up my mind, but it seems acceptable. The interface, graphics, and music are all excellent, but the actual gameplay just seems to be space 4X mush. Not particularly good, not offensively bad or bland. Unlike galciv 2 they put some space butter and space cinnamon (Melange?) and space sugar in the mush.
Spec Ops the Line: Only played a tiny tiny bit of this. Can't comment on the story at all, third person shooting seems average.
Quantum Conundrum: Only played a tiny bit of this too. Seems a bit questionable given Portal 2's nearly infinite maps with the map maker and Steam Workshop, but the puzzle mechanics are a bit different so eh.
Magic the Gathering Duels of the Planeswalkers 2013: Like the other DotP games, perfectly serviceable computer Magic with pretty good AI to play against. Unfortunately the decks seem to rely on creatures heavily unlike the first of the modern DotP games, which actually has some spell-heavy decks and had things like dick-ass counter and discard decks.
Krater: Bleh. Played a bit of this, didn't leave a good impression at all. Unless they dramatically improve this it's largely a waste of time and money. Extremely dull loot, whole lot of nothing story, and plain real-time party action RPG combat.
Sins of a Solar Empire Rebellion: The last time I played a SoaSE game was the original with no expansions. This includes the content of all the expansions of the original game and the new Rebellion content. That added shockingly little. Wasn't much of a fan of SoaSE in the first place and this didn't particularly change my mind about it. Kinda slow paced compared to other RTS games (Which this is), kinda slow paced compared to turn based 4X space games which let you hammer end turn if nothing's going on (Though this does let you increase the game speed in singleplayer on the fly), and not even particularly good space porn with combat taking place in a 2D plane and ships moving to maximum range and then sitting still and firing back and forth. Unless you absolutely must play a space RTS I'd recommend playing Sword of the Stars 1 or even space mush Endless Space.
Max Payne 3: Eh! Wasn't really a fan of the story, didn't like the move to Brazil, didn't like the in-game cutscenes replacing the voiced comic panels. All that said I still mostly enjoyed the shooting in the game. You seem to have less bullet time than in the previous Max Payne games but I still had a good time shootdodging around and blasting people. If you want some third person bullet time shooting it's entertaining. The graphics are also nice and run surprisingly well on modest machines, surprising for a Rockstar game.
Fieldrunners: DON'T DO IT. DON'T BUY IT.
Alan Wake's American Nightmare: Improved combat over base Alan Wake, and a shorter and weirder adventure. If the first game didn't fizzle out on the story I might've preferred it to this, but since it DID American Nightmare's a bit better due to better gameplay. Still not sure I'd really recommend it unless you're interested in it already.
Gratuitous Tank Battles: Like Gratuitous Space Battles only even worse!
Warlock Master of the Arcade: Surprisingly excellent turn based fantasy wargame. Has been patched and improved over time, too. Highly recommended!
Toy Soldiers: Action tower defense where you generally have to take control of a tank or a turret and blow things up yourself. Not a horrible game, but given the choice I'd recommend Orcs Must Die 1 and/or 2 instead. If you've already played them and want more action tower defense however then this is worth a look.
Binary Domain: Surprisingly good combat and entertainingly shlocky story which is told shockingly well. Amazingly enough they realized the pace for an action video game story shouldn't get too drag-assy and it moves at a good clip. Has a cover system which is mostly a trap to fool you into using cover instead of KILLING GODDAMN ROBOTS. Has multiple endings and a loyalty system for party members related to it. It's like what Mass Effect would be if Bioware wasn't so bad and could focus on the action and story pacing. Well worth checking out if you can stomach third person shooters.
A Valley Without Wind: Pretty goddamn boring. Supposedly they're making a sequel/remake/something which will be added for free to anyone who bought this version. Hopefully it'll be better.
The Walking Dead: Mostly good story mostly executed well with pretty good voice acting, and absolute shit for adventure gaming. Next to no puzzles and the few puzzles that are there are the easiest things in the world. The much touted C&C is mostly bullshit and amounts to a few cosmetic dialog changes and VERY few scene changes, and nothing really changes the ending of the series. If you like zombie apocalypse stories it's worth either youtubing or picking up for cheap during a Steam sale, but avoid it if you expect any amount of adventure gaming or decent C&C.
Legend of Grimrock: Really good game which is let down a bit by the heavy emphasis on waltzing during combat. Turns it into more of an action game than I would've liked. Still, entertaining dungeon design and I mostly liked their rule system. If Jaesun put a gun to my head and said I'd die before he'd let a 2011 JRPG be named RPGotY 2012 I'd vote for this and not feel too bad about it.
Lunar Flight: Fly a lunar lander around! Scan things! Pick up things! Land on other landing pads! Refuel! Then try it all with the in-cockpit view! It's an inexpensive and fun indie simulation if any of that sounded good to you.
Shoot Many Robots: Hold the D key and LMB until you win! If you start not to win as easily and sometimes have to do something drastic like hit W, change equipment until fixed. Still played some hours of this, not entirely sure why. I think the explosions and sounds were pleasing and let me vegetate while playing. It's alright.
Hack, Slash, Loot: Kinda like if FTL was a fantasy dungeon crawler with worse combat. Almost entirely based on luck and moving around seeing how things play out. I like luck in my videogames (For example, the modern Xcom) but luck with no way to influence the game yourself is a real bummer. Without FTL's combat and ship management this isn't worth it at all.
Rayman Origins: Surprisingly good platformer. Bunch of secrets and hidden goodies to collect. If you like 2D platforming definitely check it out.
Age of Empires Online: Age of Empires with grinding! Oh boy!
Cubemen: Kinda-sorta tower defense like thing. If you get it in an indie bundle and like tower defense it's worth a look but apart from that I wouldn't say it's worth it.
Stacking: Only played a very little of this but my eyes glazed over so... There's that.
Containment the Zombie Puzzler: Eh.
Really Big Sky: Randomized, but the bit I tried of it seemed eh.
Realm of the Mad God: F2PMMOARPG eh.
Alan Wake: As mentioned in American Nightmare above, the possibly entertaining story shits itself in relatively short order and then you run from light to light while the same shadow monsters try to club you to death over and over. Even with my complaining it was ok enough I finished it and the DLC. Just don't think I'll ever really be interested in replaying or recommending it much.
Crusader Kings 2: Took some learning to get the hang of it but it's pretty damn cool. At 56 hours played I might've played more CK2 this year than anything else. Strangely most of that was shortly after I first got it, and I haven't really gone back to it since. Why? Not entirely sure since I had a good time.
Jagged Alliance Back in Action: Didn't think it was a 2012 game but Steam says it is so eh. Not as bad as the Codex generally says but still pretty flawed. Enemies seem to be able to take way too many shots. I know the guy is wearing a helmet but my sniper just shot him in the head with a .50 cal sniper rifle!
Kingdoms of Amalur Reckoning: Only played a little. Seems a bit better than a Fable game but similarly shallow and actiony.
The Darkness 2: Didn't like it one bit. AI was poor, weapons weren't very interesting, had a few annoying graphical issues, super powers were mostly dull after you used tentacle kills a couple times, didn't give a damn about the story.
Titan Attacks: Good Space Invaders-like. Nice use of an upgrading system, it's possible to fuck yourself up with a poor build or poor performance so you can't finish a campaign.
Pineapple Smash Crew: Kinda sorta Cannon Fodder-y only randomized space ships and not as good. Eh.