. . . the case is extremely strong that Moses married a black Cushite woman from the Cushite civilization south of Egypt. This understanding not only fits with the details of the biblical text, but it also fits the historical picture of Cushites in Egypt at that time and with the way the text was translated and understood by the ancient writers.Read the whole thing for further thoughts from him on the broader issue of interracial marriage from a biblical perspective.
See also Hays's book, From Every People and Nation: A Biblical Theology of Race, published in the New Studies in Biblical Theology series.