Honestly, I've spent most of 2012 catching up with 2011 games, 2011 was an amazing year, I don't think 2012 will come close to equaling it. That said....
Final Fantasy XIII-2 improved upon everything that made the original (IMHO) so awesome. Except for maybe the characters, I am not crazy about Serah and Noel was a wimpier version of Snow. Oh, also the music was kind of mixed. The gameplay was great, especially with the battle system being tweaked to fix a few of XIII's problems. Running into Noel, Sazh, and Snow were great moments. What really made the game for me was the more open level design. I liked XIII's level design for that game, but mixing it up for XIII-2 was the right call.
Journey was an awesome 2 hours. In fact, I am hesitant to even go back to it, because I enjoyed my first play though so much.
Kingdoms of Amalur was one of those games that was fun, I enjoyed it, but not enough to download the DLC or go get some more of those trophies, but it did make an enjoyable 20-hour hack and slash through the main game.
Mass Effect 3 might be my favorite game of 2012, so far. It was pretty much everything I had hoped it to be (though it did feel a tad short). I wasn't pissed about the ending like some people. It seems like everyone had very different experiences based on what they chose in the previous games, so they did a great job of incorporating all of that. The writing was superb, Garrus and Tali especially, with their scene together at the end of the game, as well as drunk Tali and Garrus' "this is my favourite place on the Citadel".
2012 games I'm working on right now: Gravity Rush and Sorcery. Both are promising, and should probably bump Amalur off my shortlist.