Read it here: http://www.counterpunch.org/2013/01/01/hollywoods-nigger-joke/
From the essay:
We realize that all that had gone before, the shots of the black slaves, the sad music, the spiritual music and lyrics—all of that was just a set-up, a pretext. The real text, the underlying message was the punchline that Blacks in slavery were fools and cowards.
Throughout the rest of the film, this is Tarantino method: begin with a serious treatment, suck the audience in, and then, he hits you—Bang!–with a punch line that catches you off guard. The problem with the ethnic joke is that the joke is always on the black man, who, has no recourse to respond.
Where I saw the film, at the AMC theater, in Emeryville California, the audience was the same one that had voted for Obama. When I waited in the long line to see the film, people’s faces were glowing with expectation. The hype about Jamie Foxx and Sam Jackson and Kerry Washington was like voting for a Black man for President.
But after seeing the film, their faces were empty, their eyes were blank. Sure, they had laughed at the scatological humor, had flinched at the gruesome ugly scenes, had been insulted by the self-deprecating humor, and had been lifted up by the antics of the “bad nigger”...
For many of them, Tarantino had delivered. In essence, they had their cathartic laugh, and yet they still felt dirty from the guilty pleasure. Their empty faces were drained understanding. They had been used, and they were beginning to know it. You could see that they had been bamboozled.