There have been a number of reports that Google PR is updating. Yes it looks so. A small change has been seen already, here's the current stats;

Current PR = 4
New PR on toolbar = 3
Predicted PR from iWebTool = 5 (4.6)
Unable to see any PR from datacentres (seologs.com)

I will look again in a few days to see what has happenned if anything.