To begin, i should note that prior to reading Badiou's book, much of Deleuze's earlier work had remained mysterious to myself. Thus, i am not in much of a position to offer any real challenge to Badiou's interpretation of "Difference and Repetition" and "The Logic of Sense." Regardless, if nothing else, the interpretation that Badiou gives is clearly presented. Although this sounds trivial, the clarity in this book is appreciated in a genre where clarity if usually disregarded, and unfortunately, often for mere stylistic (and not philosophical) reasons. Thus, because of this "Deleuze: The Clamor of Being," although dealing with difficult topics, can be understood by anybody with some knowledge of Deleuze, even if this knowledge is not extensive.
The clarity of the presentation, however, almost seems too obvious. That is, the way in which Badiou describes Deleuze's "philosophy of the One," and the quotes that he extracts to demonstrate this claim, make this thesis to be obvious to anybody who has read Deleuze. However, clearly this is not the case, as Badiou himself recognizes that this book should shock those who take pride in Deleuze's "schizophrenic" aspect. Thus, merely taking Badiou's interpretation of Deleuze, and the fact that so many thinkers have overlooked what he presents as information that should be clear to any reader, this gives me the uneasy feeling that he, and not these other thinkers, has missed something fundamental in Deleuze's thought. This, of course, necessitates a re-reading of Deleuze's own work, something that "Deleuze: The Clamor of Being" necessitates, i believe, for anybody who overlooked the first time around what Badiou reveals as self-evident to any acute reader.
As a previous reviewer pointed out, Badiou gives little interest to Deleuze's work with Guattari. However, although there definitely is a schizophrenic aspect to this work (especially in "A Thousand Plateaus"), it seems as if the fundamental concept of the Body Without Organs corresponds in most, if not all, ways to the concept of the virtual/ the One. Badiou does occasionally use ideas expressed in Deleuze's work with Guattari, especially "What is Philosophy" concerning the status of philosophy, however, he fails to cite these sources.
Additionally, it seems to me as if the interpretation that Badiou gives to Deleuze's work indicates more of a pantheistic vision that one that indicates transcendence. Of course, there is a bit of irony to write that Deleuze has "transposed transcendence beneath the simulacra of the world, in some sort of symmetrical relation to the `beyond' of classical transcendence," but regardless of the irony, the very idea of Being as univocal and as One chimes much more with eastern worldviews than western Platonic and Christian ideas of transcendence. This especially seems to be the case when we consider Deleuze's work with Guattari in which all strata (that is, all different properties of the world that surrounds us) are merely "coagulations, slowing-downs on the Body without Organs."
Finally, even if Deleuze's ontology indicates "heirarchical thought," this doesn't mean that Deleuze's task, therefore, is to "submit thought to a renewed concept of the One." In fact, it seems to me as if there is a crucial distinction in his work with Guattari between "methodological" claims and ontological claims. Rather than encouraging us to employ reductionist schemas in our analyses of any given system, the very title "a thousand plateas" indicates that we need to take into account as many different aspects at work as possible-- biological, economical, polotical, geological, etc. (this distinction between a methodology of multiple aspects of reality and an ontological expressing only One fundamental reality is continued in Manual Delanda's appropriation of Deleuze and Guattari's thought in "A Thousand Years of Nonlinear History.")
Despite these further considerations that would have been made necessicary had Badiou taken into account Deleuze's work with Guattari, "Deleuze: The Clamor of Being" provides a tremendously useful, and strikingly clear, interpretation of Deleuze's independent work to the point that it necessitates a re-reading of this work.