Wired is running a story inspired by the level of gore in the recent Wolverine game that wonders: how much is too much? It mentions a study we discussed in February which indicated that violence tended to interest gamers less than other characteristics.
"... the longer you play a 'twitch' action game, the less you notice the cultural content — the gushing blood, the shrieks of agony. You're too busy focusing on the gameplay. I noticed this with Wolverine. For the first hour, I found the deranged bloodshed both shocking and exciting; it made me feel like I 'was' Logan, the grunting, killing-machine character from Marvel Comics' X-Men universe. But as I became more expert, the cultural shell of the game boiled away. In a sort of staring-into-the-cascading-numbers-of-the-Matrix way, I found myself looking past the visible aspects of the game and savoring the underlying, invisible mechanics of play. ... The game became pure physics and algorithms: Vectors, speed and collision detection. The gore had become mostly irrelevant."

http://games.slashdot.org/article.pl.../05/22/0737232