There are hundreds of reports across the web about a Google PageRank update. Most of you know, I am not a fan of the PageRank score displayed in the Google Toolbar, but I report it anyway, because I report what SEOs care about, which I determine by looking at threads in the forums.
What is interesting about this PageRank update is that it comes less than a month from the last PageRank update. The May 2009 PageRank update took place on May 27th/28th. This one started last night on June 23rd.
Normally, toolbar PageRank updates happen about every three months. So to see a widespread update like this just a month later, is interesting. Outside of that, I don't have much more to add.
Forum discussion at WebmasterWorld, Google Webmaster Help and DigitalPoint Forums.
