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.
Another concern about this project has to do with preservation: I wonder to what extent digital preservation is covered in the settlement. Will this collection exist 50 or 100 years from now?