As a writer, I have a special loathing for what Google Books does to published authors, believing that it violates copyright and that if any other company had done what Google did, they would have been sued into bankruptcy several times over. Don’t get me started on the settlement. If you don’t know about this, the settlement BINDS copyright holders who DON’T agree to it. If you don’t opt out, that means you’re in. I’m not sure how that’s legal. (Could I pick a hot guy, put an ad in the paper to let him know I’m marrying him and if he doesn’t show up, that means he agrees?)
However, for out of copyright books, it’s beyond awesome. I can use it for research, and it’s great for books so old that the copyright has expired and they are hard to get.