My partner really cannot do maths
I live in Japan at the moment and see a few mixed race couples around the traps (Japanese-white, mostly). The cultural differences are huge and most of those couples don't seem happy. I don't know if this is the mixed-race issue particularly, or rather: a) very different cultures b) the white person involved is usually an arsehole c) the white person is very much isolated from their own culture, but it makes me suspicious that mixed-race couples can work.
I'm not American though, so I don't know what the term "race" means in connection with black Americans. I can't imagine that they actually have that different a culture to whites. I read squashed's comment as simply saying that mixed-race couples suffer more shit, and therefore are less likely to work out. I have no idea if this is controversial or not, but it doesn't seem to be. My parents always used to ask me "Your girlfriend isn't aboriginal is she?" Obviously there would be trouble if she was. Similarly, my high-class girlfriends' parents always hated me, but people from the same class tended to not mind.
As for class, I didn't say anything about inherent qualities. It just tends to work out that way. I haven't tested the theory enough times to be sure, it's just my impression. And (as a commy Italian-migrant friend's parents told me once), it doesn't matter what you do now: it's where you came from which determines how people of a different class will view you. I like to hope these differences can be surmounted, but I have never seen much evidence of it.
You could make a pretty decent case that they are two different bands
I love Led Zeppelin, too (and if you don't, Brock Sampson would like a word with you), which my girlfriend considered terribly lame when we started dating, but she's since become a big fan. In return, she introduced me to the Cure, and a lot of alternative music. (Geeky side-note: Porl Thompson, longtime Cure guitarist, toured with Page and Plant during their "it's not a reunion-tour").
I think the problem for both bands lies with classic rock radio formats. The only LZ song you'll ever hear is Stairway to Heaven, which, frankly isn't all that great. With PF, you might get Comfortably Numb, Another Brisk In the Wall, or Wish You Were here, but that's it. You'll never hear any of Syd's stuff, or the pastoral psychedlicism of Grantchester Meadows. There are huge back catalogs by both bands that show a lot more range and invention.
Anyway, collecting music is one of my passions. The back room of our house is crammed with over 1,250 cds, so chances are, I'll have something you'll like. I can't stand most top-40 music, mainstream country, or jazz for white people, but I don't know if I'd break up with anybody over it.
Restless ambition is still the best aphrodisiac I've ever encountered.
My problem is when class differences become the basis for class snobbery. I don't mean relatively minor misunderstandings - those are just part of being humans with different experiences - but rather serious disdain or lack of any desire to understand someone because of her or his class background. I haven't run into too much of that, but enough to know I that I really don't like it.
Linnaeus, I grew up dirt poor and this really resonates with me. I'm married, so no more dating, but this is a friendship deal-breaker for me. People who look down on me because I'm not particularly well-traveled or because I have never tried certain kinds of food (although that list gets smaller all the time) or whatever can go fuck themselves. I seriously had a roommate in college who could not grasp the fact that I had never been west of Ohio (which is no longer true). She thought I was bullshitting her. It was truly an astonishing display of ignorance, and furthered my already strong belief that she was an asshole.
I also am wary of people who are concerned to the point of being patronizing. I mean, I grew up poor, not under a rock. I am not stupid (this is especially frustrating when it's people at grad school. Hello, I got in to this school also, and it was certainly not because of my looks and charm). It's possible to be sympathetic to the problems of a different socioeconomic class without being a condescending asshole.