I remember reading somewhere that Quentin Tarantino has a MENSA-level IQ, so I refuse to believe that he put all that effort into Django Unchained just to guilt white people into writing more reparation checks. But is the director trying to convey a subtler lesson about race relations with his latest film?
Well, let's be frank: no one is going to change their views on race based on Django Unchained. Sure, there are some cringe-worthy scenes exposing the brutal cruelty with which blacks were treated during those times, such as the bit where we see two slaves fighting to the death for their owners' entertainment. But all in all, the movie, like most others by Tarantino, is an exercise in indulgence. If there is a message to it, the message is: "I like Spaghetti Westerns." The horrors of servitude are played out to serve the emotional payoff of this revenge fantasy, and, in that sense, Django is a perfect spiritual brother to Inglourious Basterds, where (spoiler alert) a WWII platoon composed entirely of Jews (and one redneck) use machine guns to cast Hitler's ass into oblivion. What could be more satisfying?
And yes, as far as wish-fulfilment goes, this latest movie, too, is very satisfying indeed. Some of the slave-owner characters are among the most disgusting villains to ever stamp the silver-screen, and the protagonists are cooler than a dead polar bear's ass. Even the Germanic/Viking tale of Siegfried and Brunhilde is used to increase viewer's sympathy toward the heroes, and boy, does it work. I was rooting for Django like he was my brother running the 100-yard dash at the Olympics, and, to cap everything nicely into a powder-keg of awesomeness, the movie ends with my favorite song of all time.
But nothing is stated about slavery that most people haven't already figured out. Namely, that it wasn't good. Tarantino is more worried about cramming references to classic Spaghettis (such as the part when Django dresses like Lee Van Cleef's character in La Resa Dei Conti) than about laying some wisdom on some of America's darker years. This obsession with homage goes so far, actually, as to work against the movie, because it replicates Italian-style westerns so well that even their post-modern structural weirdness and lack of a coherent pacing are present.
And that also explains the movie's underlying theme, because a lot of Spaghettis (like A Fistful of Dynamite) also had social/political undertones, which, just like in Django, didn't go beyond plot devices to capitalize on the viewer's sensibilities.
In that, the movie really is no different from Jackie Brown, another of Tarantino's efforts to proeminently feature the "N"-word: It's pure entertainment. That doesn't mean it takes slavery lightly, because the director, as I've said, pulls no punches in showing us the absolute ugliness of that culture. It just means that that absolute ugliness is used as a catalyst, because everyone in their right minds hates slave-owners, so you'd be hard-pressed to come up with more fitting villains.
In conclusion, I would advise you to turn off your brain before watching Django Unchained for maximum enjoyment of the experience.