My daily browsing has come across an idea I haven't seen before, though it has been mentioned on LW occasionally. Created by Giulio Tononi, the basic premise seems to be that consciousness can be quantified, by measuring how much information is contained within the overall patterns of a system in excess of the information contained within its subsystems - that the whole is greater than the sum of its parts.
The general idea doesn't seem to fall prey to most of the more obvious flaws that theories about consciousness tend to end up suffering. But I'm far from an expert in the field, or potentially related fields such as considering Φ's possible use as a basis for developing AGI/FAI. So: what does the wisdom of the crowd of LW have to say about this concept?