Nice comparison, though I hate it when graphics look like they were drawn to scale, but actually aren't. (The Google indexed pages bar would have to be more than 10 times larger.)
More on topic: Whether you can compare the index sizes or not mostly depends on their signal to noise ration. Given the number of Google search request per month and assuming and average of 5 viewed results, you can put a lower bound of 99% of pages that are never seen by anyone. As the search results should greatly overlap the actual number of relevant sites is probably orders of magnitude less than 1%.
Comments
Nice comparison, though I hate it when graphics look like they were drawn to scale, but actually aren't. (The Google indexed pages bar would have to be more than 10 times larger.)
More on topic: Whether you can compare the index sizes or not mostly depends on their signal to noise ration. Given the number of Google search request per month and assuming and average of 5 viewed results, you can put a lower bound of 99% of pages that are never seen by anyone. As the search results should greatly overlap the actual number of relevant sites is probably orders of magnitude less than 1%.