168,178,719 as of last Friday according to Google Books. Geoffrey Nunberg is worried:

Whether the Google books settlement passes muster with the U.S. District Court and the Justice Department, Google's book search is clearly on track to becoming the world's largest digital library. No less important, it is also almost certain to be the last one. Google's five-year head start and its relationships with libraries and publishers give it an effective monopoly: No competitor will be able to come after it on the same scale. Nor is technology going to lower the cost of entry. Scanning will always be an expensive, labor-intensive project. Of course, 50 or 100 years from now control of the collection may pass from Google to somebody else—Elsevier, Unesco, Wal-Mart. But it's safe to assume that the digitized books that scholars will be working with then will be the very same ones that are sitting on Google's servers today, augmented by the millions of titles published in the interim.

That realization lends a particular urgency to the concerns that people have voiced about the settlement —about pricing, access, and privacy, among other things. But for scholars, it raises another, equally basic question: What assurances do we have that Google will do this right?