that might be a bit harsh to say,..but i agree for the most part japanese games are more polished than the american games. i would say even the best american made game still falls short when compared to the best japanese made game. Of cousre this depends on category,..as i know alot will say but look at halo!
that said i feel the american developers have the fps category on lock. But just in general the japanese games are just made better.
