from 4-5 days i am facing a problem that my websites ranking suddenly down and it have out of 500 but today morning again it showing with in top 10. is it sign of PR Updates
My SERPs have been fluctuating, though not to the extent yours have (and I'm lolsandboxed). But wasn't there a PR update already, very recently?
SERP update is like this, for few days you are out of serp and you are back again for some changes ofcourse... its either backlinks or PR or SERP ranking.
Sheesh.. Where do these guys get this kind of information? If Google fluctuates a little bit with their search results only means that the ever constant change in their algorithms are taking place. Google dance (or sandbox or whatever SEO webmasters call it) is not an indication of a PageRank update! These people should have themselves rehabilitated just to get off and wake up from the PageRank addiction that they're experiencing.
I think the PR had updated 3 days ago, i checked all my sites, 5 new site get PR0 , another get 0 to 2 , other two still PR3 and PR4 ..