According to CNET(Reuters) [news.com.com] Google is going to release a new book search on Thursday, Oct 6th.
Google founders Sergey Brin and Larry Page will host a press conference on Thursday to demonstrate the technology at the Frankfurt Book Fair in Germany, an important showcase if the Internet search engine is to recruit the heavyweights of the book publishing industry.
The new service, dubbed Google Print, is incorporated into Google search queries. When users search for many book titles, they get "book results," URLs that lead to book excerpts, at the top of the list of ordinary search results. The book excerpts will carry a link to buy the book from a choice of online book retailers.
Although I did read on the gogle print site that publishers can send them their book and have it scanned into their results at no cost, so it would appear that Gogle are indeed using their own data set.