Also, tangential, but something I was thinking about today. The reason why "intention" matters when it comes to something like Borat might have something to do with mirror neurons. If racism is not institutional (i.e., unavoidable and something structurally embedded that we all on some level partcipate in), but exists in individual events or "evental sites" or what have you, maybe it's important to remember that humans can, and always do, call upon a "sense" or set of sensory input that is now being understood by neuroscientists as a fundamental function of cognition.
Mirror neurons are believed to be the structures that process input in such a way that they what give people the feeling of "rapport" with others. It's a sort of meta-structure that we don't quite understand yet, but that seems to have lots of promise. So when some people watch Borat and perceive racism, instead of satire, maybe it has something to do with not being in tune with Borat (or more in tune, as the case may be.)
Maybe this doesn't make sense the way I've said it, and there's obviously no way to test my hypothesis (yet), so it's not scientific, but read about mirror neurons here if you like that sort of thing:
http://en.wikipedia.org/wiki/Mirror_neuron