Horrible gruesome violence that fails to shock

Noah's blog made me think about something my dad said last night as we watched tv. It went vaguely like this:
"Whats up with all these shows?" he said. "Theres all this blood. Last night I was flipping channels and I saw some show where the guy was dying in the operating room and fluid came out of some iv etc. etc etc. It's not even hbo or anything, its normal primetime tv."
I flipped the channels. CSI: blood and fluids all over the floor. House: Blood and fluids being talked about, and occasionally all over the floor. Heroes, which I watched the night before: telekinetic scalping, after which point blood and fluids got all over the floor.
I realized that in fact, TV does have a lot of blood/fluids on it. Yet, it seems completly natural. The average person watching primetime tv probably does not even realize the amount of blood that gets shown it. It is only when someone fresh appears on the scene that they suffer the initial reaction "hey, theres a lot of violence."
I think initially, someone tried to be just a little more edgy, a little more dramatic, and so included a small amount of blood in their tv drama. This was HORRIBLE SHOCKING, and served its purpose. Yet, over time, people became desensitized to this small amount of blood, and so the only way to elict the same reaction was to up the ante with more blood/violence. Over time, we arrived at our present level. Its probably likely it'll still raise.
It's a lot like swearing. Swear words have power because they shock. at an older time, if someone swore, something SERIOUS had happened. Now, swearing seems so common as to be common everyday vocabulary that is nowhere near the levels of offensiveness that it once was. Over time, we build tolerance, and the only way to elicit the same reaction is to gradually increase.
Is it a bad thing? On one hand, we could trivialize violence or language, but on the other hand, we aren't shocked by as much. Maybe a higher tolerance prepares us for the "real world", where there are no network censors to tone down the violence or language.