Few Months Back I Post Google Page Rank Caculation Formula . PR Updates will takes Place on google for Every 45 days are known as Google Dance. Now PR Update is going on
Google technically defined It is the period that Google is their rankings, and results fluctuate widely for a 3 to 5 days.
The name "Google Dance" was in the past used to describe the period that a major index update at the time of Google search engine are implemented . These major Google index update occured on average every 36 days or 10 times per year. It was easiest be identified by significant changes in search results, and by an updating of Google's cache of all indexed pages. These changes is record for every minute. it took several days to finish the complete update of the index.