I attended the Computers in Libraries Conference in Washington D.C. last week. The biggest impression that was made on me of anything I heard was the "Library 2.0: The Challenge of Disruptive Innovation" presentation and paper by Paul Miller, who is described as a "Technology Evangelist" for a company called Talis.
The idea of integrating Amazon and Google into a library OPAC means thinking of them as partners and collaborators, rather than as competitors. If a library patron sees a book on his local library's catalog, the library should provide him with the option of purchasing it with a few mouse clicks, if he doesn't want to (or can't) physically come to the library and borrow it.
Chad Boeninger's presentation on turning online research guides into Wiki pages is something I'd like to explore myself, because I started years ago with the guides on printed sheets of paper, then moved on to pathfinders on Web pages using Dreamweaver and FrontPage. Using Wikis seems attractive because of the possibility of several knowledgeable people contributing to the subject, especially if some of your patrons are experts in the field. It may provide an easier way to prod them into collaborating on the project.