I play GTA IV very rarely due to easy boredom
but when I do, and I kill people in it, it doesen't bother me because I know the difference between real life and a video game entity
sure, it looks like a person, and has fake blood like one, but something would have to be REALLY realistic to effect me in that way
however, it does remind me of how when I used to play MW2, the realism of the game would actually mess with me outside of the game, I stopped playing very soon after getting that type of effect
EDIT:Beachbum, I lol'd