I have been seeing updates to the toolbar for some weeks now ... but these are not across the bar updates, but mostly updates that reflect pages such as listings or links pages going to 0 and into the supplementals.
Many pages that are not related to link selling or trades are losing
PR ... and understandably ... a real estate listing, for example, or a product listing has a relatively small chance of being visited by a random surfer than more general content pages, and I see this
PR update reflecting those sorts of adjustments as well.
As others have noted, recent
PR updates do not seem to be affecting SERP positions or traffic.
I would never say, "dont' worry about
PR" but I would say there is less reason for concern than there was once ... as long as a site's SERPs and traffic are stable,
PR changes are not a reason to panic.
The supplementals are also not the anathema they once were. I don't want to start an argument here, but just to note that as Google gets more and more tight with
PR many legitimate content pages (such as product listings) are going to remain in the supplementals without detriment to the site.
Cheers, MJ