Two of my sites dropped PR, one from PR5 to PR4 and another from PR2 to 1, what does it mean? What are possible reasons why my sites dropped PR?
It means that (some of) the backlinks towards your site have lost some of their weight. Has nothing to do with your site and your rankings.
It totally depends: If PR of your post pages dropped, it's because you're being a fool with the keywords you're trying to rank for and the engines are seeing your work as not providing value but trying to play the system to get $ BUT, if the PR of your domain itself dropped, it is either going through a rank dance because you're being analyzed for fishy behavior (or your site was randomly picked due to metrics of link frequency and consistency of visitors). If your domain experiences a harsh drop, clean up your site of bogus material such as copied articles and other garbage such as spam links and make sure you create new baccklinks with the utmost care. i've had blogs go PR4 to PR1 to PR2 to PR5...and I did nothing to it...
There are several reasons for this, it has happened to me as well. Just like google is known for its google dance, it will at times fluctuate with its PR as well. As it is trying to analyze the worthiness of your site by analyzing the quality of your links and other factors, you could see this go up and down. Given the PR I assume these are older, more established sites? DId you rankings go down? Just adding a few quality links will bring your PR back up.
Most of my competitors got slapped too and their PR went down by one too. I still rank the same as I did before. Might have to do with keywords on link backs, I have used the same keyword on a lot of back links.
Could it had anything to do with, i created three new pages and have a link to them from the home page? Since the new pages are PR0 could that had caused the PR drop?