It seems that Google’s been busy doing something this month. A number of people on one of the forums that I hang out in have said that their sites suddenly dropped in PR. In some cases they went right down to PR0.
What’s going on?
It seems that not enough people are seeing changes in their site rank for this to be called an early page rank update. The consensus seems to be that Google is updating backlinks. Backlinks are links to your site from other sites. Apparently Google does mini updates of these frequently, but when they do a large back link update they are likely removing duplicates and or spam or splog site links. Perhaps that’s why some people’s PR ended up going down. it’s possible that they had a lot of splogs or spammy sites linking to them.
It’s hard to say what’s going on because Google doesn’t announce it’s updates, and tends to keep it’s formula’s for determining page rank and other things related to a sites listing in their search engine secret.