Some reasons why books are still relevant:

1. I find it easier to read a lot of text on paper than on standard LCD screen, maybe e-books on a e-ink display will change this.
2. Book tend to describe the big picture and some good practices, that is really good when you need a quick start or a new view.
3. Google is really good when you need examples on specific topic, but not for the big picture.

But a book will never take you all the way, it will just push you in the right direction.