I know. I wasn't including general "animated porn" in this. Or even "real life" porn, for that matter.
And, yeah, Ethnic Cleansing as well as that JFK shooting simulator fall into a similar category of artistic irresponsibility. We've all had these moments where somebody is telling bad (read: racist/sexist/vulgar/etc.) jokes and you're all laughing because they're genuinely funny but then somebody goes "a little too far" and it stops being fun. It hits too close to home, so to speak. I think that's what can happen in these situations. I can't draw the line but I know when it's been crossed. And it's usually when you first see somebody give that uncomfortable smile where they only show the top row of their teeth.
I'm the biggest fan of "edgy" humor but even the most open stand up comics who work with racial humor all the time probably cringed when they saw the Michael Richards fiasco, regardless of their color. Our personal "lines" might be in different places but I think most people have them.