Access to (and belief in the possibility of gaining access to) resources seems like the greatest predictor and greatest stumbling block for all demographics that are historically "underprivileged".
Prejudice, racism and discrimination are not necessarily the leading factors in determining a group's economic success or failure except where these factors directly determine a group's access to resources like education, transportation, and even grocery stores.
Part of the problem we are looking at here is how the basic issues get ignored, while political band-aids are applied in attempts to provide a balm as a big fix.
It's a case of treating the symptoms and not the cause.
There are too many bright and active people in our world for me to imagine that in 20 years things will be worse along demographic lines. I have to think that sooner than later, we will recognize that communities without grocery stores - and where few people own cars - need to change logistically so that people aren't shopping at corner stores for food, overpaying, and essentially being stuck in a situation where there is no potential for moving up. This, of course, is just one example of how poverty becomes systemic and perpetual. It is a practical problem, born, perhaps, from racism, but now culturally entrenched.
It is difficult to predict which direction any part of our society will go in the next 20-30 years. But certainly there are some worrying trends with respect to African Americans. Young African-Americans have fewer educational and economic opportunities, and there are movements in schools across the country that would only reestablish de facto segregation, even in communities where it was largely overcome. In addition, budget concerns have local, state and federal government officials looking to weaken the social safety nets for many poor people, a population where African-Americans are disproportionately represented. An improving economy would certainly help, but it seems many Americans today have adopted the stance that racism is no longer a factor in African-Americans' lives, or at least not one that government ought to use its power and resources to attack.
I think that 20 or 30 years from now the African American community will be much more stratified than it is now. Overt racist barriers will continue to fall, thus helping those who are already in the middle class. But more barriers, not necessarily cause by racism, will hold down those who are poor. Their status will get worse. So there will be much more of a gap between haves and have nots.