Komodo_Tale - 8:52 am on Jun 23, 2006 (gmt 0)
Google does a lot of load sharing based on data draw and geography. Based on the latest and on previous Google updates/dances/serp-changes I know that certain datacenters tend to be more predominant than others in my locale while the results that others reported during the same periods weighted towards different data centers. Of course, this is a rough observation and I do not expect Google to share a detailed explanation any time soon. Then again, I could be completely wrong.