Because many Google users would not find this amusing and would "assume that this reflects a political bias on our part," Google has kindly and defensively provided an explanation:
The Google engine ranks pages in order of popularity. Pranksters adept at Google-bombing can influence those rankings. Google doesn't like such pranks but doesn't want to "alter our results by hand in order to prevent such items from showing up."I thought it was interesting that Michael Moore is second in those results.
Via Nancy and the SF Chronicle