Google: Books of the world, stand up and be counted! All 129,864,880 of you

[kjk]

http://booksearch.blogspot.com/2010/...e-counted.html

Well, it all depends on what exactly you mean by a “book.”
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Counting only things that are printed and bound, we arrive at about 146 million. This is our best answer today. It will change as we get more data and become more adept at interpreting what we already have.
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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.

Interesting look at what counts as a book.