When you are of the opinion that George W. Bush or "Shrubya" is a "miserable failure", you could find confirmation for this by googling for this and this truth would be on top both in the Google, Yahoo or Microsoft search engine. Effectively it is a prank. It is not what you really want to find and Google announced it has worked on an algorithm that will prevent a Googlebomb in future. Effectively making the word a misnomer it is now more correct to call it a Yahoobomb or even better, a Microsoftbomb.
In an article in the Guardian, the fear is expressed that by manipulating rankings in this way, Google will exert its power and be able to manipulate what is seen as true. At issue is that the reason why Google defused this bomb was because people believed it to be true because Google said so... (there is no such thing as common sense as common sense ain't common)
In many content projects, bots create links to websites they hope to make more relevant in the eyes of the search engines. This type of vandalism resulted in a backlash where Wikipedia now indicates to search engines to disregard any and all links and thereby invalidating the basis on which search engines operate. When Google were to have algorithms that filter and punish this type of SPAM, it would lead to a more sane environment.
Google is open about its intentions. Microsoft is open about its intentions as well; as long as it discriminates against its competitors like Wikipedia I will be happy to use Google knowing that Google is kept honest by having competitors.