Been discussing Nihil Unbound in my lectures recently. The book gets interesting, in my opinion, from chapter 5 on when Brassier brings in Laruelle and notions such as determination in the last instance. Laruelle has this interesting reversal of a transcendental deduction whereby the object imposes itself to the subject and ends up determining itself in the last instance. It is a true reversal of the Ptolomaic counter-revolution. Brassier puts this together with the move towards extinction that is carried by each craving for knowledge. It is a drive towards a low degree of being or towards being colonized by the object, being occupied by the thoughts imposed by the objects that called us (he mentions Lévinas Autre in this connection to refer to the way the objects call upon our attention) and that extinguish us by promoting in us a turning into something else. Brassier brings in Heidegger's being-for-death then to join together the drive towards objects and the drive for death - the thirst for knowledge is an extinct against other instincts.
It is interesting that becoming is a central part of the argument. Not because it takes us somewhere commendable or because it is itself good. Brassier rejects the connection between life as a flux of becomings and something desirable in itself as a connection that grounds no more than a vitalism he finds unattractive. (Analogously, he rejects the good beyond being that Lévinas associates with radical ileté while accepting that the the Other calls upon us,) His theory of becoming has a Schopenhauer tonality: they bring in extinction while we cannot in the long run escape from them as they are connected with the underpinnings of our curiosity. Becomings are not the ultimate flag for vitalism but rather they pave the way for extinction.
Laruelle's starting point is indeed very different from that of Meillassoux. He doesn't seem to want to struggle arms in arms with correlationism but rather to start out from a different story altogether (non-philosophie). His other scenario is that of objects promoting thinking rather than that of the ancestrality (or of the absolute beyond correlation). Brassier tries to take this determination in the last instance of objects over thought not as a sign of the final triumph of a better form of life but rather he takes disenchantment of nature seriously and sees no way to halts the path of enlightenment. Objects are not going to save us because they impose themselves to us, they are no saviours - there is no redemptive post-humanism here. Because objects in their anonymity and their degree zero of being seduce us, we are already all dead and there should be no political project to rescue us in the name of vitalism. There is no other project to follow but that of the enlightenment. That is, the one of extinction through knowledge.