Google usually updates page rank 3-4 times per year.Page rank is not the only thing Google looks at when they determine how well a site performs in the rankings.A site with PR 0 may be higher in the rankings as a PR 5 site.So, don´t look too much on your page rank.

I believe it was yesterday

Well, PR updation takes place every after approx three months if you are doing well in building quality links then you may sure get PR incresed in next updation.......I will suggest not stop worrying about PR and focus on getting higher rank on SE's because ranking on SE's is more important.

My PR went up yesterday in toolar, for what it matters (zilch). Enjoy it while it lasts, because Google has finally realised that PR is not worth the effort and is going to phase it out.

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