I’ve always thought it looked strange to see people referred to in print as Black or White rather than black or white. For example consider this sentence: “A black guy was walking down the street and he saw a bunch of white guys standing around.” That looks fine, whereas “A Black guy was walking down the street and he saw a bunch of White guys standing around”—that looks weird to me, as if the encounter was taking place in an Ethnic Studies seminar.
But maybe I’m wrong on this. Jay Livingston argues that black and white are colors whereas Black and White are races (or, as I would prefer to say, ethnic categories) and illustrates with this picture of a white person and a White person:
In conversation, I sometimes talk about pink people, brown people, and tan people, but that won’t work in a research paper.
P.S. I suspect Carp will argue that I’m being naive: meanings of words change across contexts and over time. To which I reply: Sure, but I still have to choose how to write these words!