Google Update in June 2011
According to reliable sources Google has been preparing a few interesting updates  for June 2011 including public toolbar PageRank update . Dejan SEO team has observed and reported an strange data rollback in Google Webmaster Tools (backlink profiles) and unusual shifts in search results which seem to have reset at some point during the first week of June. We’re yet to see if this was a temporary test or a glimpse of a more permanent change. Some SEO experts speculate new interface and algorithm changes are about to be released.
Update: PageRank updated on 27 June 2011
-  - http://blogs.forbes.com/quentinhardy/2011/06/11/google-scale-changes-everything/
-  - http://www.seroundtable.com/google-pagerank-update-13463.html