A fascinating UPI story gives a bunch of statistics about interracial marriages from the 2000 US Census. The two biggest pieces of news are:
The article goes on to discuss other statistics, but it never addresses the long term effects that these disparities will have on the US population. The overall racial (and mixed-racial) breakdown of the population won't be affected much, but any traits that are particularly strongly represented among black women or among Asian men will become diluted over the generations.
Via Andrew Sullivan.