Stilla,
Ok, mostly answering cuz you are with a cracka, and I like my women like my coffee.... hot and dark!
With that said, I can say that the cultural differences in general aren't so bad. It depends on how much you are a product of your culture. I find that many black jw's aren't THAT black. But no matter how cosmopolitan we are, we still are influenced in significant, if subtle ways by our culture.
Unfortunately I haven't dated a sister, so I don't have any good ideas for you on traversing the jungle fever thing.
Most of the heat comes from other people. You probably won't get much hassle from his family, if he is as big of a hippy-dippy as you describe. Some white people will likely not like it. But probably at least not to your face. Most polite white folks are scared to death of seeming racist. (of course I have never had to deal with white folks as a black guy, so I could be way off base here) He will probably get more heat from the brothers. I could see a few of them wanting to bust his balls and cock-block a bit when they see you two strolling down the street.
The a-number one thing that determines a successful relationship in my mind is having the same values; having the same ideas about right and wrong. The areas where this is critical and most problematic are in money and parenting. Compare his financial habits to yours. Compare his upbringing to yours. These should be at least compatible. These things sound mundane, but become incredibly important and divisive in the midst of a marriage and family.
The interacial stuff doesn't seem to get in the way to much I have found, if you both have a good sense of humor about it. My wife can do a complete theatrical reading of Coal Miner's Daughter, and bought me SlingBlade on dvd. I refer myself to the foreman of the drywall or landscaping crew. Sometimes I refer to our home as the Alamo. We all have a good laugh about it.
CYP