Google Books continues to expand their range of available material and it’s great to see. Not only does it increase access to information but, for the material that you have to purchase, it increases the efficiency of the market for information. Previously you had to buy an entire textbook, or purchase a membership at an academic library, to get access to snippets of the text. Now you can buy just that snippet that you want on Google Books! Who does that help? Well, pretty much everyone in the market for information, actually.
If I could only buy textbooks in entire units then I probably wouldn’t be willing to purchase the ones which only had a small chapter of interest to me. I miss out on reading the chapter and the publisher misses out on selling me that information. By allowing me to purchase a smaller quantum of information their profit goes up and so does my happiness. It’s surplus increasing to sell me the book in smaller chunks and better for everyone.
Google Books: daily decreases of deadweight loss.