Badiou's work is often both refreshing in its Platonic instance of the reality of abstractions and the importance of ontology of events and truth-procedures, and infuriating in that he often makes bold claims without explicit argumentation using a methodology of suture to lay philosophy out as meta-truth procedure. This book is short, but dense and often obtuse: for one, it is a collection of essays that can be divided into four categories: 1) polemical essays, 2) essays of commentary and support, 3) examinations of major categories, and 4) philosophical prescriptions. The last category, that is to say, the only argument that Badiou makes that is fundamental to his system lies in the last essay, "Politics as Truth Procedure."
This is largely a book whose roots lay in a suturing of politics to philosophy, but as the critic of Badiou has said, François Laruelle the demarcations of this suture is actually not as apparent as Badiou wishes. That aside, the sustained polemic against political philosophy, which Badiou seems to largely see as ethical and managerial at root, begins with 'Against Political Philosophy' in the first essay. Admittedly, when one can parse the idiosyncratic way that Badiou defines the state and events, his take-down of various forms of liberal political philosophy, such as the Levinasian reification of the other, Rawlsian "reflective equilibrium", Habermas's 'communicative ethics', Rorty's evocation of a 'conversation of mankind' moves it away from the purely ethical and the largely linguistic turns. These rhetorical defenses of pluralism are actually a defense of a homogenization of a liberal meta-state, but unlike critiques from the right, the ontology of "Being and Event" lingers in such a way that moves one to a nearly Maoist conception of the fidelity to the idea, and an Althusserian notions of structures, but which emerge from fidelity to events.
Now this makes sense in the larger movement of Badiou's work, but this is without Badiou's normal systemic lay-out of the position. However, the particular valorizing of Sylvain Lazarus and his ambivilent statement about Jacques Ranciere can seem hyperbolic even to those very familiar with contemporary French thought. Furthermore, as I have hinted at, it seems that even in Badiou's larger work, the argument for the suturing of evental politics to philosophy is actually quite thin in the larger work, and if that fails, so do most of these polemics.
Badiou, obviously, is refreshing, rigorous, and often insightful, although one sometimes suspects a formalization of Maoist impulses lie deeply within the text. People unfamiliar with Badiou's thought SHOULD NOT start with this text as it simple structure is actually predicated with much deeper knowledge of Badiou's methods and the philosophers in which he is in dialogue.