The impression I've got so far is that a lot of the text sounds like it could be mathematics (mostly either topology, full of Cthulhu-esque 'tendrils' and 'wormholes', or dynamical system theory, with implications of catastrophe theory -> Apocalypticism), or it could be physics (especially ideas about entropy, heat death and so on - again, a definite eschatalogoical vibe), or chemistry, psychology, sociology, politics, history, anthropology, archaeology, metaphysics...but what it actually is, is pure occultism masquerading as all these various disparate topics. It's Abdul Alhazred as an insane 21st-century polymath academic, which I suppose must have been the effect Negarestani was going for all along - and it's superbly done, I have to say.
Something else that's struck me about the book is its 'meaningful meaninglessness' (edit: oops, pre-empted there by slim!) in that it's a bit like listening to someone sing a song in a language you have just the barest grasp of - most of it seems to be meaningless, but by the overall tone of the song you can tell it's a song of love, loss, revenge, celebration or whatever, which is backed up by the occasional sentence or phrase you can decipher. Or maybe it's more like someone who speaks English but is rapping incredibly quickly and segues immediately from one track into the next without pausing for breath, heh.