PyMaemo has some components which are maintained by third parties (for example, PyGTK and most packages also found on Debian and Ubuntu). These already have their own documentation, so we just reference the existing documentation.
For the components produced by us, we also maintain the documentation. Note that some of our own components still lack proper documentation and examples.
The community is invited to improve and contribute to the documentation, and even write new content. That is the main purpose of keeping most of the documentation on the Wiki.
For more information on how to get involved with and help PyMaemo, see Get Involved.