It shows that the Google is still the leader, may be because of those Linux clusters and might be the reason Microsoft's Steve Balmer jumping in to bed with Novell. Hoping to sue Google, may be not he does not have enough hair to pull.
Here is the figures;
Example: An estimated 3.0 billion search queries were conducted at Google Search, representing 50 percent of all search queries conducted during the given time period.
Top search engines in September 2006
Find more search engines performances on the report.