There is plenty to critique in this book, and I think the urge to critique is heightened by the author's ubiquity.
For one, Fanon is deeply misogynist and homophobic. He writes that it is in refusing to acknowledge the black man that the white man strips him of his subjectivity, and yet he writes nary a word about the black woman. The greatest irony of the book is that the chapter entitled "The Woman of Color and the White Man" is really a chapter about how black men perceive black women, and its central point is this: Black women bear the children of white men because they believe that by whitening their race they shall earn prestige, and in doing so black women abandon the role they should be playing assuring black men of their virility. (No wonder later writers like bell hooks would lash out against Fanon.) His remarks on white women and homosexual men are equally subjugating: They both want black men to rape them.
For another, Fanon is a trained psychiatrist, and as chapter titles like "The Black Man and Psychopathology" indicate, he is invested in using the psychoanalysic practices of people like the Freuds, Jung, and Lacan to analyze the relation between colonizing and colonized peoples. Perhaps it's just that psychoanalysis has run its course in cultural theory -- or perhaps that it's just become so banal, which amounts to roughly the same thing -- but I found the long passages on dream interpretations rather dull and not terribly persuasive. Appiah concedes this point in his introduction to the Grove edition.
These criticisms aside, however, what I think remains most valuable in Black Skin, White Masks is the fact that at heart it's a small, personal book -- a meditation on the author's own experiences as a black male intellectual -- that can't quite live up to the reputation it has earned as the record of an entire generation. Despite the "vintage" gender politics and analytic practices, Fanon's book conveys a palpable sense of subjective hurt, and also a surprisingly conciliatory desire to forge new, mutually beneficial relationships with white people. Of course, the second best reason to read the book remains its influence; after all, it's hard to read Glissant, Silverman, Hartman, or many others, without first making a pit-stop here. Recommended for literary and cultural historians.