Scott Aaronson's critique of Integrated Information Theory:
http://www.scottaaronson.com/blog/?p=1823At most, I think IIT is a step in the right direction and probably necessary for consciousness (though not sufficient).
Some of the axioms IIT is based on may also be false. In particular, it's not obvious to me that consciousness is (i) integrated and (ii) exclusive. For example, in 'The Society of Mind', Marvin Minsky argues that the brain is made up of a large number of autonomous processes which interact with each other. I would further argue that there is no evidence either of one central process or a singular conscious process [1].
[1] At first, it might be hard to imagine two independent conscious processes in the same brain. But consider the work of Roger Sperry with split brain patients
https://en.wikipedia.org/wiki/Split-brain .