Rust Guide
Honest initial impressions from my quick glance.   This guide is confused.   It reads at times like an informal conversation... lots of exclamations.   That's pedantic,  the real confusion comes from the target audience.   As a programmer, I want as little cruft as possible.  Get me to examples and how this differentiates from C.  As a non programmer, teach me the basics of types and logic.   
From that thought,  it's failing at both.  As a programmer, stop talking to me informally and redefining types as one liners.   As a newbie, you're explaining basic shell constructs as if I don't know, then trying to sum up strings in a one liner.   
I know it's an early draft, and I know Steve is an awesome dude.  My advice - figure out your audience or else break into two guides.  Be terse with me, be overly explanatory to a beginner.  This now seems to sway on both sides of that line, and likely will frustrate both groups.