There's a difference between not wanting to marry someone just because they're black (or white, or Asian, or whatever "race") and not wanting to marry someone of a different ethnicity because you want to preserve your culture and your heritage, and someone of a differemt background would simply not be able to relate things that are extremely important to yo. The first case can be racist (but if it's just about attraction and not rationalized on the basis of race, then it is not, obviously), the second is definitely not.
Am mixed myself, by the way, but wouldn't marry a non-Jew myself (but I don't care whether she's Ashkenazi, Mizrahi, Ethiopian or something else).
Like I said, I'm less opposed to certain ethno-religions preferring to keep families in the religion/ethnicity, though they shouldn't excommunicate or otherwise kick out people who don't marry within the group. The smaller the ethno-religion is (to a certain extent, I wouldn't want inbreeding), the less objectionable it is.
And the fact that you'd marrying any variety of Jewish person, regardless of ethnicity, makes it a little less objectionable.
My faith isn't also an ethnicity, but I would prefer to marry a Mormon, of any ethnicity. But considering where I live, the most likely candidate for someone I can actually meet is probably white. Even though I'm attracted to white, black, Hispanic, Asian, and other women.
