Google has a ton of private data that should not have been indexed, in their index. It's just that no one has thought to search for it yet. (See: http://en.wiki

Google has a ton of private data that should not have been indexed, in their index. It's just that no one has thought to search for it yet. (See: http://en.wikipedia.org/wiki/Johnny_Long http://en.wikipedia.org/wiki/Johnny_Long) A single public index would expose this data to stronger analysis (or even plain reading), not just Google search queries.