"After we exclude serials, we can finally count all the books in the world. There are 129,864,880 of them. At least until Sunday."
Google counts all the books in the world and explains how it did it. This does not however represent all the human knowledge which may be contained in mediums other than books. Yes, that includes blogs too.
[Link to Total Number of Books in the World]
But Ars Technica thinks Google’s methods and numbers are bunk.