QT's interview: "It's not blood that people have a problem with; they have a problem with the color red, all right?" Tarantino says. "And all of a sudden when you take crimson red and turn it into black oil yet intellectually you know it's still blood, it's a little different. To just drown the American audience in blood is to win the battle and lose the war. But also even if I could've gotten an R with the color version, once I discovered the black- and-white, I would've gone to the black-and-white anyway. It kept it fun."
Other notes from the interview: 'So the Japanese will be treated to a bit more gore, and, in one key difference, the American/European version goes to black-and-white for the bloodiest stretch of the samurai battle while the Japanese version stays in color'