Saying they’ve unearthed a very specific 129,864,880 books (and growing since tallied on Sunday), Google today blogged their method and rationale for counting every book the world has ever produced.

Google (GOOG) has its own special counting method, which may end up being controversial to the world’s librarians who’ve standardized on ISBNs (International Standard Book Numbers).  Google contends that ISBNs (and their SBN precursors) have been around only since the mid 1960s, and were not widely adopted until the early-to-mid seventies.   ISBNs are also only used for books that may have a potential for distribution in the Western World.  Google is trying to index every book ever created from Gutenberg and beyond.

What about other well-known identifiers, for example those assigned by Library of Congress (Library of Congress Control Numbers) or OCLC (WorldCat accession numbers)?  Nope, those don’t work either.

There are issues with multiple editions of the same book with different forewords for instance.  Some count these once, while others count each individual edition.  And then you have hardcover and softcover versions which often carry separate identifiers. In the near future of electronic books, these differences won’t make much of a difference (and can conveniently be all-included).

Do we need another method of cataloging books for the electronic world?  Google explains its methodology here.

But the bigger question: Why is Google so enamored with books?

Besides the very noble goal of wanting to index the world’s information for all to use, they also sell a lot of books through different fulfillment houses (see below) through its Product Search service.  Google likely gets an affiliate cut of the business it sends to these retailers and makes a healthy amount of money from pointing customers there.

Update: Google was nice enough to inform me that they don’t exact a fee (yet) from sending over traffic to sites like Amazon.

Google also is rumored to be planning its own eBook venture which would allow it to sell books electronically like Amazon (AMZN) and Barnes and Noble (BKS) now do.  Google’s edge lies in the older, more obscure works which it has scanned into its own library (for indexing and searching!).  Google’s product will likely be web-based so it won’t limit the reader to one platform.  This later advantage might be something consumers will embrace as they move from platform to platform (though Amazon and Barnes and Noble are making efforts to be just about everywhere.

In the end, like a lot of Google’s humanitarian efforts, there is a cold hard cash money angle that they’d surely like to exploit.  But first they’ve got to get past the librarians.