One site I have a link on has dropped over the w/e from a 7 to a 4..

But the DP thread show a blog that had dropped.. It likely to be wide spread but not seo site hence less of buzz so far..

The sites i've seen I don't wish to post but i'll try today to find one...

Matt Cutts has Said :

Looking over that thread, it looks more like one person said that their PR4 went to PR0? The first sentence I saw on the PR0 blog was "Looking for notebook batteries, cell phone batteries, and external batteries for all your consumer electronics." Other posts are marked as sold yet the links flow PageRank.

So it's just this blog isn't trusted as much in Google; it's not an actual PageRank update.
Taken from: http://www.seroundtable.com/archives/015704.html#comments