PCI uses general terms. At one point PCI (section 11.5b) mentions file comparisons, but in that context it seems to me that it's speaking to the original form of FIM which involved computing hashes once a week and comparing results to determine if the file changed rather than comparing the contents of the file. That's how I read it anyway.
For the first version of FIM we will not have this capability, but of course we'll see how people use the feature and what more they think would be valuable and consider that going forward.