I dunno. Depends on the game I guess. Lemme give some examples of some games I've played in the past and my view on them.
Soldier of Fortune. When this game out, I remember the dismemberment of enemies was a big deal. For me, it was just a lame gimmick and was overdone so I disabled it. I discovered with violence off wherever you shoot a beam of light shoots out of the spot you hit. This was ten times cooler than the gore and it was easier to see where you shot someone. Plus, it was cool to see beams of light shooting out of your enemies heads when they got shot.
Duke Nukem 3d One of fave games to this day, and I love the blood and violence in it. For me, it serves a purpose. It's pretty darn funny. Once I discovered gibbing enemies made Duke spout audio comments, I was an rpg addict.
Half-life I felt the blood and gore wasn't overdone in most places and where it was overdone it was bit amusing. Sniper rifle in TFC, anyone? You headshot someone and their entire body explodes.
Mortal Kombat 3With the pansy way Lui Kang was screaming the whole game, I wanted about 5 gallons of blood to spout from him.
Max Payne Turned off the blood here...can't remember why. Probably didn't have a valid reason to keep it on.
Ok, after carefully looking over these 5 games, I guess I only want blood in games if it is funny. Kinda twisted, isn't it. Oh well.