The Parallax View is a remarkably good book. I recommend your reading it. It is his way of talking about the Anagogic Swerve, i.e. the veering from one viewpoint to another with respect to the same subject matter. It is a discontinuous crossing between viewpoints. Since it is one of the few books on the anagogic swerve I spent a long time reading it and got a lot out of it. This book is much more substantial than most of the other books I have read of his which are mainly the books on his re-interpretation of Lacan. This book too makes the convincing case that Lacan is really just Hegel in disguise. Marxists are realizing that Hegel was a much deeper thinker than Marx and so are returning home to Hegel in order to get the necessary depth to deal with the demise of Soviet style communism.
It more or less crystallizes Zizek’s method of turning everything upside down and emphasizing the gap that appears in the transition. Of course, this is Nietzsche’s old trick. But Nietzsche did not concentrate on the gap being produced in the process of turning things upside down. Zizek concentrates on that gap and its irreconcilability. But this only works because Nihilism is there structuring the dualities within the Western worldview and thus producing the gap between the radical and artificial nihilistic opposites. Zizek makes use of all these structural transformations but does not really explain why they are there in the first place to be made use of. His normal engagement is to say why something is really the opposite of what it appears at first glance, and this sameness is what gives the nihilistic effect. Zizek recognizes the nihilism and the sameness, but often reduces it to a joke which emphasizes the turning of from one perspective into the other unexpectedly.
For the most part Zizek seems to be right about the curious inversions. And many of the twists and turns are quite unexpected. But once you understand them then you wonder why you did not think of that yourself. So Zizek turns out to be very insightful reading concerning cultural and social phenomena. He clarifies issues between Kant and Hegel as well as elucidating Lacan as the anti-Derrida along the way. Lacan is famously obscure. And Zizek’s interpretation of Lacan is compelling if for no other reason that one feels at least that one can understand him for the first time. However, there is no way to verify Zizek’s interpretation of Lacan, so one just has to take it on faith that it is close enough to the mark to make sense to the uninitiated. However I have not started the work of trying to verify his interpretation as yet. So we may see some surprises. For instance Merleau-Ponty said that certain things were in the Husserl archive that no one else could find. But I have yet to hear of any Lacanians protesting. But that is probably because they don’t understand their master well enough to protest.