No Google haven't updated page rank. I think you site will be crawled recently and results in improved keyword position in serp's.
Google does keep on updating.... Dont think google is not watching your site..... they keep track of every site and mostly they will rank relevant content only on the first page.... and i have also noticed major changes on the ranking on my site happens on Friday.....
Every PR checker seems to be on the blink: Google data centers are either "Down," "Off", or showing a PR of "0".
I think there is some major SERP update today. I am today witnessing one of my site ranking on # 1 page for very high competitive keyword. It was on 3rd page before.
i look now and my all sites pr 1 and 0 :S didnt understand and it showed google.com pagerank too 0 :S
Google keeps on updating their internal PR values, and SERP's is almost dynamic and updates all the time.. However, just noticed that most of Google DC's are down right now..!
In the future you should use the search function. Below you will find 4 threads about pagerank updates that were started less than a week ago. http://forums.digitalpoint.com/showthread.php?t=1441754 http://forums.digitalpoint.com/showthread.php?t=1443924 http://forums.digitalpoint.com/showthread.php?t=1440952 http://forums.digitalpoint.com/showthread.php?t=1441987
Yeah.. there seems to be some problem with the Data centres.. Even google.com shows unknown/10 here http://www.checkpageranking.com/index.php?name=google.com&links=1
Mypagerank.net is only giving the PR. These sites like checkpageranking are validating PR and as Google is only using www.google.com so its says the without www is unknown See example http://checkpagerank.ws/?domain=google.com http://checkpagerank.net/index.php?name=google.com&links=1
I've noticed the same here with all of my domains, it's only showing PR value for the URL's set to be main ones even with or without the www
LIke most of the people already said, SERP is always changing. So far my sites hasn't changed it's pr.