Very little in this book is new to me, nor are the ways that the pieces assembled all that new to me. But it's _really good_, and the approach avoids all of the activist screechiness that I sometimes find off-putting, even when I agree. Saguy is also very careful with what she says and how she presents her sources, thus no irritating "but that's not really true" in my brain while reading it.
It's not long, especially if you just read the main text -- the back matter is a substantial fraction of the book. I highly recommend it; she's an academic that can actually write, which is all by itself a rare and beautiful thing.