Martin Aspeli wrote to the plone-users, developers and documentation lists this morning with a "loud cross-post" in which he outlines a number of critical gaps in Plone documentation, and asks for our help in filing them:

Plone's documentation has grown tremendously over the past two years or so since Plone 2.0. We recently had a documentation sprint to try to organise and improve what's there, and there's a lot of ground that's been covered.  Maintaining and quality-assuring all of it is a challenge, and we need more help in this area.

However, there are a few gaping holes as well. Sometimes we have documentation that's incomplete or of questionable quality. Sometimes we have no documentation at all. We'd like to change that, with the following call for help.

Martin asks that we take a look at:
http://plone.org/development/teams/documentation/missing-documentation

where he lists a half-dozen of the most critical documentation needs, outlines very clearly the work that needs to be done, and suggests the best ways to get started.

Martin emphasizes that you don't need to be a Plone guru to write good documentation --  merely willing to step up and learn as you go.