Nubian has a great, debate-inducing post on the term "people of color." Personally, I like the term, but honestly, I've never thought much about it. Some of Nubian's readers object, feel that it excludes white people (which makes them defensive or absolves them of repsonsibility to be part of the solution to issues that revolve around race/ethnicity/color), casts white people as "colorless" or "raceless," or normalizes a racial binary of white/of color. I am most sympathetic to that last point, but using the term "people of color" did not/does not create that binary--it exists anyway, whether we reference it or not. The solidarity implied in "people of color," that sense, on some level, of a shared experience is valuable.
But I don't discuss this nearly as well as Nubian and I haven't thought it out clearly. Please read her post.