I visited many website today and found this PR updating is not too good for previous well ranked websites. I checked major seo websites and other well ranked websites and I noticed most of all websites PR went down.
Recently Google had changed algorithm and very strict about paid linking. In Google webmaster tool they introduced paid links form where you can write about any website that selling or buying a link. Mostly paid linking is used to manipulation of search engine. I visited iwebtool.com; they are also selling links and found that their page rank goes down from 7 to 4. This shows Google is very strict about paid linking and in future Google may penalize website that involved in paid linking.
Seems like there is a Page Rank update taking place now that seems to be impacting sitesthat sell links. Can't say that we were not warned about this. Danny Sullivan wrote Official: Selling Paid Links Can Hurt Your PageRank Or Rankings On Google over two weeks ago, and now it appears many sites are getting hit with a drop in Page Rank.
Here is a list of some sites, including major publishers, who seem to have taken a hit overnight: