An example of a game that really stumbled on this point was the PS3 exclusive Haze, in which every rebel was a saintly freedom fighter and every soldier was an evil, demented jerk. The result was a game in which the "moral dilemma" that was supposedly at the core of the experience just ended up having no impact at all.
Essentially, I'm wondering if we'll see some aristocrats who are good people, along with some peasants who are not, etc. If it's as black and white as "rich = evil" and "poor = good", it would undermine what looks to be a really well developed game world.