I notice that you have the Charisma Myth on your book shelf as well as The Design of Everyday Things. Two excellent books. If you want to get more value out of books, then I recommend taking notes. I started doing this recently with books and organising them on Evernote. It’s why I love Amazon kindle because it has the highlights features. I take notes and highlights on different books and then move them over to my Evernote.
With paperback books I use sticky notes which can also be added to Evernote via a camera.