Bloodborne still tops the list for me at the moment, I'm also loving Fallout 4 lately. MGSV is in a weird place for me where I played and enjoyed many hours of it but it also heavily disappointed me. Witcher 3 I got to the cold land and I was pretty much over it already did not enjoy combat enough in that game to care anymore.
Bloodborne by far. Really dug the atmosphere and mechanics. Level design stayed pretty great throughout as well so that's a plus.
Nothing else really comes close. I love Steins;Gate, Mushihimesama, and Under Night In-birth but they're only really new to western countries so I don't count them the same.
Splatoon easily of what I've played from this year so far, but I still haven't played Bloodborne, Life is Strange, Rocket League, Fallout 4 (just got a PS4 yesterday), or Xenoblade Chronicles X.
Right now I'm torn between Witcher 3 and Bloodborne, nothing else comes close. I know I'll enjoy Fallout 4 but it won't compare. Had a great time with Rocket League as well.
Halo 5 has the potential to be the best shooter this gen but it has a severe lack of content at the moment. It probably won't be the game I want it to be until next spring.
MGSV is probably my most disappointing game so far. It has the best open world gameplay this gen but it's so repetitive, I really dislike the level design, and the obvious things like the lack of story and the cut content hurt it as well.
I'll need to finish episodes 3, 4, and 5 of Tales Borderlands to see if it makes the list in any place. In case it doesn't, Everybody's Gone to the Rapture will take the place in the third row.
So far, it's between Bloodborne, Witcher 3 or MGS V. There are some games that I haven't had a chance to play yet that may be put on that list, such as Until Dawn, Transformers Devastation and Dragon Quest Heroes.
Bloodborne. In terms of mechanics, level design, presentation, lore and lack of all those things that annoy me in so many AAA games (fetch quests, hand holding, tutorialisation, tons of cut scenes, pointless collectibles and so on) it has no equal.
honorary mentions: fallout 4(really need to spend more time on this), tomb raider(ditto), bloodborne, axiom verge, also divinity original sin and wasteland if you count those as this year
Bloodborne and Rocket League stand taller than anything else this year. Cities: Skylines also has a spot in the top league. I've heard really good things about: Undertale and Axiom Verge that I believe to be true.
I have no idea what my frontrunner is but I do know that the battle to avoid falling into honourable mentions (or just off the whole list) is going to be tough this year.