Really hard to summarize my thoughts on this book in a brief fashion. I took a lot of notes while reading. Poulantzas is one of the most interesting Marxist theorists of the state that I've read, carrying on the insights of Louis Althusser. He's also very good at diagnosing the Ideological and Political viewpoints of the petit bourgeoisie, as he demonstrated in his book on fascism.
However, I strongly disagree with his view that the determinant factor in whether a worker is technically part of the working class is whether their labor is "productive". A huge swath, a numerical majority, of the workers he places in the 'new petit bourgeoisie', are absolutely actually part of the working class. His points on the ideological and political effects of the class positions of mid level managers, engineers, and technicians are well taken, those are very real and have actual effects on class struggle. But the idea that elementary school teachers, trash collectors, and millions of retail and service workers aren't part of the working class because their labor doesn't add surplus value to commodities is just untenable. We see these workers participate in the class struggle equally as much as "productive" workers, there is no vascilation between the proletariat and the bourgeoisie as there is with engineers and managers. I think the more determinant relation for class structure is that of exploitation. These workers do not direct others, they can't hire or fire, their surplus labor is extorted from them. In these ways they are all workers, and they participate in the class struggle alongside other workers. So labeling them petit bourgeois makes no sense.
These disagreements aside, this is still a more interesting and rigorous examination of the phenomenon commonly called the 'PMC', albeit in a now somewhat outdated conjunctural context of 1970s France, than we see from most modern authors. The sections on the relations of the various fractions of the bourgeoisie to the state is also particularly interesting.
Good book, worth reading even if I have some rather major disagreements with some of it's points.