Favorites in no order:
Skyrim - An open world rpg that always surprises and has ample amount of content to be constantly involving. Interesting mythos and world, great setting, allowance of variance in play style, with a very refined take on the "the more you do it, the better you get at it" that remains consistently fun. The best rpg this generation by my estimation, that I have played.
Saints Row 2/3 - If there was one word I'd use to describe these games it'd simply,"fun". But for all of its fun, these games are also some of the better written, and more interesting takes to come from games in years. I said before that Saints Row 2 is easily the most forward thinking game I've ever played, I stick by those words. Saints Row 3 has a unique take on the different genres that make up games and ultimately how shallow a lot of games are. Saints Row is the one series that manages to make me laugh, have fun, and tickle my brain all in one package.
Diablo 3 - clickclickclickclickclickclickclick.
Super Mario Galaxy 1 - Not a reinvention of the wheel by any means, but by far the most interesting reinterpretation of a classic game star in ages. All the mechanics...just work. The level design is top notch, you'll forget you're hustling for stars because each chapter of a level has a unique take on the stage that will send you to a different part of the level rather than redo-ing what you just did five minutes before. A platformer with immense variety and fun, this game makes me smile like a five year old. One of the few games I can play today and it'll instantly make me feel like a kid again, and in a good way. Easily the game of the generation for me, and it's a shame so many haven't played because it's on Wii.
Resident Evil 5 - Say what you want about this, but it really clicked with me. Enough that I got everything within a week, after clocking 50 hours. I rarely do that with games, and RE5 managed to work with me in a way few modern games do: make me a completionist. The level variety, intense moments, and co-op were its greatest parts. I'll admit the bosses could have used work, but they were the only major flaw in a sea of awesome. Plus, ONLINE MERCS.
Super Street Fighter IV - I have not clocked more hours with any game this gen than SSFIV.
Virtua Fighter 5 - Shame online is dead, because this is still the best fighter I've played this gen.
Dragon Age: Origins (pc) - As a big fan of Baldur's Gate turn based, drag to select style of combat, I really enjoyed DA:O . I thought it was the most refreshing wrpgs in ages, even if the overall package was a retread in many ways. Still, it had a lot of ideas that single-handedly fix the "Bioware problem" so to speak. For instance, there is no good or evil, you merely have an approval system, forcing you to play a role, learn the characters' personalities, and appeal to them. It's far more fun than whatever outdated Paragon/Renegade system Mass Effect has.
Dead Rising - I still think the sequel, while good, does not touch on the original's wit and unique spin on this formula. Dead Rising is a brutal game that takes some practice and memorization to be good at. It's the exact kind of game that appeals to me: a very short, but very open game that places emphasis on replays, leveling up, and constantly finding alternative ways to play. I played this game 5-6 times in a row when I first got it, and it was a very nice welcome to the Xbox 360 for me.
Bonus: Ghost Trick, Starcraft 2, Catherine, Super Meat Boy, The Sims 3, Deus Ex: Human Revolution, Elite Beat Agents, Mega Man 9, Batman: Arkham City and Asylum, Red Dead Redemption, HL2 Episodes 1 and 2, Portal 1/2, Blue Dragon, Lost Odyssey, Warriors Orochi 3, Dynasty Warriors Gundam 3, Dynasty Warriors 7, Fallout 3, SMT: Strange Journey, Crush, Tactics Ogre: LUCT, Ys 1&2 psp, Ys 7, Ys 3 psp, Phoenix Wright games, Ninja Gaiden 2, and more.
Combined with the portables, what a great generation if you want to talk about just GAMES and not the other bullshit (DLC).
Disappointments:
- Grand Theft Auto IV - Starts out pretty good, then turns to shit.
- SSX - Boring. The demo is better.
- Final Fantasy XIII - Horrible pacing, but great battle system, horrible story, but great presentation. A game that for every step forward has one step back.
- METAL GEAR SOLID 4 - Shit, shit, shit, shit.
All of these games I can think of good things about. All of them except MGS4. What an abortion.