did a list not too long ago so here it is - best of the seventh gen. 360 and on later only, nothing pre-2005. also had a top 100 all-time but that's way out of date now.
Omitting most previous gen ports, and only one entry representing each series except Metal Gear.
~ Honorary mention to Rock Band 3 (Harmonix, 2010) ~
40.
Lollipop Chainsaw (Grasshopper Manufacture, 2012)
39.
Trauma Center: Under the Knife (Atlus, 2005)
38.
God of War III (SCE Santa Monica, 2010)
37.
Disgaea 3: Absence of Justice (Nippon Ichi, 2008)
36.
Back to the Future: The Game (Telltale Games, 2011)
35.
The Elder Scrolls V: Skyrim (Bethesda, 2011)
34.
Dragon Age: Origins (BioWare, 2009)
33.
Tropico 4 (Haemimont Games, 2011)
32.
Sleeping Dogs (United Front/Square Enix London, 2012)
31.
L.A. Noire (Team Bondi, 2011)
30.
Rhythm Paradise (Nintendo, 2009)
29.
Civilization V (Firaxis, 2010)
28.
999: Nine Hours, Nine Persons, Nine Doors (Chunsoft, 2010)
27.
Max Payne 3 (Rockstar Vancouver, 2012)
26.
Catherine (Atlus, 2011)
25.
Bastion (Supergiant Games, 2011)
24.
Dead Rising (Capcom, 2006)
23.
Metal Gear Solid 4: Guns of the Patriots (Kojima Productions, 2008)
22.
Grand Theft Auto IV (Rockstar North, 2008)
21.
BlazBlue: Continuum Shift (Arc System Works, 2010)
20. Valkyria Chronicles (Sega, 2008)

Story is predictable anime fare but the gameplay carries it. At the time, we were stoked to see X-Com influences in a japanese strategy action game.
19. Little King's Story (Cing, 2009)

Never played Pikmin, which supposedly inspired this. Unexpectedly solid and gratifying.
18. Assassin's Creed II (Ubisoft, 2009)

First Asscreed had the freerunning gimmick but was otherwise half-baked. The sequel gave us a better protagonist and more varied missions and settings, raising the bar that it's upcoming sequels failed to top despite the addition of apprentices in Brotherhood and some lesser feature experiments.
17. Shogun 2: Total War (Creative Assembly, 2011)

Empire has a better map to play with but Shogun improved on it in every other aspect while bringing back some missing features from Medieval.
16. Metal Gear Rising: Revengeance (Platinum Games, 2013)

Went in without expectations and now I need to look up more spectacle fighters. Blade mode sounded incredible in theory but I had huge doubts, turns out they actually pulled it off. Also 60 fps was extremely welcome after years of pushing the current consoles past their limits.
15. Elite Beat Agents (iNiS, 2007)

Simple and intuitive rhythm game with hilarious short stories. Theatrhythm is basically the same game but lots easier.
14. Nier (Cavia, 2010)

Yoko Taro is a magnificent bastard.
13. Heavy Rain (Quantic Dream, 2010)

Successor to Fahrenheit with less asspull. Admittedly not the kind of genre you'd want to catch on.
12. Portal (Valve, 2007)

It's not that overrated. Second game was just as good.
11. Saint's Row 2 (Volition, 2008)

A bit sillier than you'd expect from a sequel to San Andreas, but way ahead of GTAIV.
10. Journey (Thatgamecompany, 2012)

This one isn't overrated either.
09. The Last Story (Mistwalker/AQ Interactive, 2011)

The fundaments of a Final Fantasy game mixed with a bit of Suikoden V and an original strategic combat system.
08. Left 4 Dead (Turtle Rock Studios/Valve, 2008)

Only game I've cared to play online more than once or twice, a whole summer was wasted on versus.
07. Ghost Trick: Phantom Detective (Capcom, 2011)

Ace Attorney guy's still got it.
06. Mass Effect (BioWare, 2007)

Mechanically the sequels are superior, but it was the world painted here that made me persevere through it all.
05. Professor Layton and the Lost Future (Level-5, 2010)

Great little games to play in bursts until your brain gives up. Trilogy ended with a bang, maybe they should have stopped here.
04. The Legend of Heroes: Trails in the Sky (Nihon Falcom, 2004/2011)

Vivid and detailed world, a great journey to immerse yourself into. Shame the localisation efforts ended on a cliffhanger. [EDIT: Sequel recently announced for Steam and other digital platforms]
03. Ace Attorney: Phoenix Wright - Justice for All (Capcom, 2002/2007)

Mostly because the last case here was the best in the series, apart from that they're pretty equal.
02. Metal Gear Solid: Peace Walker (Kojima Productions, 2010)

A Metal Gear you keep playing after you've finished it. Kojima's excused for MGS4.
01. Dark Souls (From Software, 2011)

Genuine challenge and immersive atmosphere out of fucking nowhere, right when we were starting to forget about these things. I've said this before; keep your Bioshocks and trippy color games, this is vidya as an artform.