The US has become a lot less racist over the last few generations. I was born in the 1970's and, although I'm white, I've tended to see a decline in racism, at least in places I've lived.
But I do see a rise in racism online, especially here on reddit, more and more often. I also see it at school (I take classes at a community college for fun).
Every now and then, it'll pop up and I've noticed a few commonalities that might lend itself to a theory. Let me lay out what I've seen.
Current racism is often targetted at the black community rather than individuals.
This is often based around a contentious point of hypocisy. For example, many redditors liked to point out that the kid who was shot in Ferguson really didn't have his hands up and therefore the entire movement was hypocritical. Of course this ignores the past few hundreds of years of institutional racism and it's impact (and we can partially blame modern media, which likes to use one act of hypocrisy to debunk the entirety of its source).
There has been an erosion of white political, economic and social supremecy. Whites still control all of this, but its in decline and that freaks a lot of people out. In an effort to preserve this, it has become worthwhile to try to diminish the value, authenticity, and sincerity of minorty culture.
Individuals are treated much more equally than in the past. So, name-calling and blatant in-your-face racism isn't nearly as prevelant as it once was. This results in a flatter society. What does that mean? It means that young people are farther away from the depths of the civil rights movement, and while they may intellectually appreciate it, it's difficult for them to truly understand the effects of such deep-seated racism. So, I think young whites look at young blacks much more equally than in the past, but this means that can't understand the need for social, political, or economic services that help support and raise the black community; think affirmitive action - almost every young person I know thinks affirmitive action is unfair, because they don't see the need for it. I, personally, do! If a white guy and black guy are running a 4 lap race around a track, but the black guy has a ball-and-chain strapped to his ankle for three laps, who do you think will win?
This is what I've noticed. It's a little different than the racism I grew up with. Some of it has always been there, like the need to devalue a minority culture, but it's now made different due to a different set of media rules and forms of communication, as well as (well, reddit, at least) idea that statitistics trump the human condition.