Only the paintjob (some reviewers have said it was 1-2 points stiffer but that could easily be QC and slight manufacturing differences)
i'm suspecting that most folks who compare the previous version of a stick that's supposed to be identical to the new one other than the PJ aren't comparing two brand new sticks. same thing with the gravity pro. my theory is that the older one feels softer because it's been used more. take into account additional stringing, break-in, etc. and it makes sense the older one is typically softer.