My fiance and I met almost 5 years ago. I am black and from New York, he is white and from the South. I have always dated inter-culturally, and so has he. When we met, we both admitted that our families were not open to the idea of our dating and were not supportive of all the inter-cultural dating either of us had done in our lives. But, we didn't care. We fell in love and have been happily together for many years and will be married in the fall.
After the first couple of years, once our families knew we were in love and were happily committed to each other, they grew to respect and appreciate our relationship. Now, they are entirely supportive, as far as we can tell. I think that familiarity has helped break down the pre-conceived notions our families had about each other. We have no children, but if we choose to in the future, I think they will have 2 sets of very happy grandparents! You just have to be true to yourself, follow your heart, and work together as a team if you face obstacles.