Japonese with some exceptions like Uncharted.

my favorite this gen is dead space 2. And new franchise is dead space.
Oddly enough inspired by resident evil and silent hill which are japanese game.

Demon Soul's as well. And that has a lot of wester tendency's.

I do like bioware/Square Enix games about equally (not all, but in general)...

So I like both. :D... I dislike somethings about both as well.

Earlier this generation I would have said Western games, but in the last couple of years, my tastes of changed and now I find myself enjoying Japanese games much more. 

The issue I have with Western game design is that once an idea is brought up, it gets reused like five times within a couple of years and that just gets boring. I also find that most Western games are technical messes, which is usually odd because they are also usually linear and small scaled.

Mass Effect 2 is a perfect example, it's a great game, I really like it, but I've used the same dialogue mechanic for like four games now and it's only been a year and half since the first. The shooting is unrefined and bland and it's extremely linear. What Western games do well is make interesting characters and universes within their games, but this is also limited to a handful of developers (Bioware, Bethesda, Valve, Naughty Dog). 

With Japanese games, this may also be because I didn't play alot of them on the PS2, I find that nearly every game I play is fresh. I liked Lost Planet 2 because despite the hundred or so shooters I've played, I haven't played a game like it before. The same thing applies to Dead Rising, Valykria Chronicles, Vanquish, Yakuza 3, Bayonetta, Nier, Resonance of Fate, Folklore, Senki no Rondo, Metal Gear Solid 4 and so on. Then I look at the upcoming games and I see The Last Guardian, Asuras Wrath, Dragons Dogma, Ni No Kuni and they are all new and interesting.

I've seen what Western developers can do and so now I'm very rarely surprised, the industry wants something different, but when a Japanese game tries, it's usually frowned upon, while games like Red Dead, COD and Rock Band keep getting high scores despite being the same game from 10 years ago.

It also helps that every good fighting game is made in Japan, I've gotten more hours out of Street Fighter 4, Tekken 6, Blaz Blu and Naruto: Ultimate Ninja Storm than I have with any other Western game, expect maybe MW2.

My answer is Japanese, though it could easily change next generation when the next barrel of innovative ideas come rolling in.

Western, don't think I've bought a Japanese game this gen!

Of course someone can check my up to date games list and correct me if they like ;-P

Veeeery soon to be untrue

I was gonna mention Mortal Kombat, but then my argument would falter... damn you for pointing it out.

i just want more metal gear

The Land of the Rising Sun.

I play both.  However, I tend to play more Japanese developed games becuase they have far more RPGs and 2D Action/Platformers, which are my two favrotie genres.  And because I like the design of Anime/Cel Shaded characters over grimdark or high fantasy.

Japanese easily.  From my memory, the only Western games I've bought this gen are: LBP1 and 2, Metroid Prime 3, World of Goo, DKCR and Bioshock 1 and 2.