I have read a few articles about digitization, future of libraries, books and Google Books Search project, and this is the first one that really goes beyond the surface of the problem and tries to compare and analyze the facts.
I agree that digitization is one form of preserving books and knowledge and no matter how rich Google is, it will only be able to scan less than 10% of books in research libraries in the US.
"While dispensing books, most research libraries operate as nerve centers for transmitting electronic impulses. They acquire data sets, maintain digital re-positories, provide access to e-journals, and orchestrate information systems that reach deep into laboratories as well as studies."
However I am a little skeptical that books will always be as many as they are today. Just think: how far are we from the generation X..Y..Z that will grow up reading only electronic texts from PCs and mobile devices? That will be the generation that will bring the end of the book, as we know it, although books as a print on demand service, probably will always be available.