Originally Posted by Apoorva
Google Dance is an old term used for the time period when Google sends it's crawler (bot) to crawl the website and check its content. It is said to be happening once in a month, but nobody has got any better idea when Google is indexing the web-page. I think, many people are concerned about Panda updates now-a-days.
My understanding is that the Google Dance is something specific that used to happen until about 8 years ago, when the database was updated every 30 days. It then took 2-3 days for the updates to applied to all sites during which time sites could "dance" up and down the rankings until all the updates were in place for all sites. As Google now updates continuously, this particular situation no longer occurs.
Sites do still move up and down the rankings but that is because of action or inaction by them and/or their competitors that is picked up by Google and because of algorithmic changes, not because of the Google Dance.