If you already own any version of the Helix book, you can download version 1.4 for free from your Sweetwater account. Here's what's new compared to version 1.3:
534 pages (45 more pages than v1.3)
In-depth analysis of v3.70’s nine new Cabs
In-depth analysis of v3.70’s ten new Amps
Complete parameter descriptions for the new effects (Prize Drive, Regal Bass DI, Feedbacker, Dynamic Bloom, and Nonlinear)
27 new presets featuring the new models in the v3.70 update
I'm particularly proud of the new presets. Even if you don't read the book, just import the presets and have fun :) All except for three of them work with HX Stomp.
I also did something a little different this time. I described the preset creation process for the new presets, and why particular blocks and parameter values were used. Also, many of these are oriented toward lead sounds. I felt the book needed more of those.
And of course, I'm always interested in your feedback for when I start work on v1.5!