I'm one of the authors of another Backbone ebook (more Rails integration focus), and I heartily recommend Nick & Chris's book. Great content, well-written, and applicable.

One of my personal principles is that I value educational content and training very highly. It's a worthwhile investment - worth the money at over twice the price.

These guys have been thinking hard about these problems for some time. You can see a lot of what Chris has been thinking/writing about re Backbone and JS practices on his blog http://japhr.blogspot.com/