After reviewing DigitalPoint Forums, I saw about 5 different threads discussing a PageRank update at Google. I am honestly not sure if this is a legit update but it doesn't really matter.
A toolbar PageRank update has no immediate or direct impact on your rankings at Google.com.
Having said that, there are a few threads at the forum on the update but this DigitalPoint Forums thread is the most active at the moment.
Forum discussion at DigitalPoint Forums.