It must be tough being Google -- everything they do is under 24x7 scrutiny, and any mistake made is jumped on by anyone looking for a story. For example, for twenty minutes yesterday morning, every Google search result said "This site may harm your computer".
It was a mistake that Google fixed immediately, and they even fessed up directly after it happened in a post on their official blog. While trying to protect the world from the "bad guys", they made a small error which ultimately made the entire internet look like spam -- woops!
"We maintain a list of such sites through both manual and automated methods. We work with a non-profit called StopBadware.org to come up with criteria for maintaining this list, and to provide simple processes for webmasters to remove their site from the list.
We periodically update that list and released one such update to the site this morning. Unfortunately (and here's the human error), the URL of '/' was mistakenly checked in as a value to the file and '/' expands to all URLs." -- Marissa Mayer