This is just a few thoughts on the topic of writing technical guides. This was intended for Basho's engineering team, but this may apply to open source projects in general.
It's commonly preached that the first step in writing is to identify your audience; to whom are you writing? This is the most well known, most repeated, and most overlooked step of writing in general and technical writing in particular. Take this document, for example. My audience is technical people who need to communicate technical information, and not teen girls, so I shy away from images of pop icons riding unicorns. I use jargon and words like "identify" rather than "peep this".