Many webmasters observed a drop of their Google PageRank. Google’s John Mueller wrote in Google’s webmaster discussion forum that this might have been a glitch and that the PageRank in the Google toolbar is not important:
“Looking at your site, it might have been that there was some kind of glitch that occurred just as the latest round of Toolbar PageRank was put together. In a case like that, you just need to wait for the next update (we do 3-4 updates per year).
That said, this is generally not something that will affect your site’s crawling, indexing or ranking, so I wouldn’t worry about it! Don’t worry about PageRank .”

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