Well-organized, challenging, enlightening, and constructive. This book and author were mentioned in the "Seeing White" podcast series, which is why I picked it up. Between Sullivan's book and the podcast, my perspective on and understanding of whiteness and my own white identity have both broadened and deepened.
(I also pocketed a few tips on how to talk to the white children in my life about race in a way that might set them up to think about whiteness in ways that I, as a kid, did not. I'm especially grateful to Shannon Sullivan for that!)