Her Salon article, which explains her central thesis, can be found here. Excerpt:
...I didn't have the heart (or the stomach) to point out the obvious: Obama isn't black.
"Black," in our political and social reality, means those descended from West African slaves. Voluntary immigrants of African descent (even those descended from West Indian slaves) are just that, voluntary immigrants of African descent with markedly different outlooks on the role of race in their lives and in politics. At a minimum, it can't be assumed that a Nigerian cabdriver and a third-generation Harlemite have more in common than the fact a cop won't bother to make the distinction. They're both "black" as a matter of skin color and DNA, but only the Harlemite, for better or worse, is politically and culturally black, as we use the term.
Let's be fair: Dickerson's article, and position, is certainly a good bit more subtle and nuanced and interesting than the somewhat shocking "Obama isn't black" soundbite that she herself uses.
But the Colbert interview is quite something and should be viewed in its entirety. Without breaking character, and playing it for laughs, he slowly and systematically takes her argument apart and then smashes the pieces into... smaller pieces.
Debra Dickerson on The Colbert Report - February 8, 2007