hypatia: Documentation is an art - much like coding. It's hard... but one of the most important things that can be done for a project. Good technical writers are rare, precious things - more power to you if you become one.
On the GNU Arch front, my gpg signing code is now in the mainline, along with enhancements from Tom - grab tla 1.2 if you want it. We support signed changesets, re-signed mirrors, and mirrors that copy the source signatures. AFAIK only monotone has anything equivalent, (although bitkeeper has apparently good integrity mechanisms - it's not signed-by-the-author changesets).