Google doesn't really do a dance anymore. They have continuously updated SERP results. The only time that google will really dance, is when they change their algo. Then there is the possibility of see'ing very large changes. I've had discussions about this topic referring to Yahoo, and nobody can seem to come up with a definate answer. They dont do it quite like google because it isn't updated anywhere near as often, and they do have larger shifts than google does now. So I guess you could say that yahoo has a dance type reaction. Google has seemed to calm down quite a lot.
Google does update the backlink results, and Page Rank about every month, so some shift is seen when they do this, but nothing like in the past.
|