Google PageRank Update 2012: Google page rank is an algorithm developed by Larry Page. Google determine page rank of a website that means importance of a sites score out of 10. Google update their page rank in approximately 6 months but it is not exact date of updating page rank by Google.
Google PageRank Update History in 2012
Confirm PR Update, May 3rd, 2012
Confirm PR Update, February 7th, 2012
Next Google PageRank Expected Dates of Year 2012
There are millions of websites around the world web and all site looking for good PR. Twitter have get very good PR that PR is 10 and also most popular sites Facebook has 9 PR. If you want to get a good Google PageRank than you need to get good backlinks from Social Bookmarking Sites. Here you found some good high PR Social Bookmarking sites List that can help you to improve PageRank of your website.
You can also know more about what is PageRank and how it is work with see following Video
How Do PageRank Update Work?
Note: This Pagerank update dates are an approx estimate itself.