Desired features in a mechanized documentation tool?

I would like some feedback on what features might be desirable in a mechanized documentation tool for Ruby and Rails. Feel free to respond on- or off-list.

  Arti is an attempt to improve the documentation infrastructure   for Ruby in general and Rails in particular. Large numbers of   Rails sites are under development. As these come online and go   into maintenance, their developers and owners will find   themselves needing better tools than are currently available.

    -- http://arti-ar.cfcl.com/

The first release of Arti (arti-0.1.2.tgz) was made about six months ago. Since then, I have been working on infrastructure (e.g., a generalized persistent storage mechanism for entity and relationship information) and looking at possible add-ons.

I am currently trying to decide where to focus my development efforts. Please look over the Arti demonstration sites, listed on http://cfcl.com/rdm/arti/, then give me your wishlist for new or modified features.

More generally, please feel free to send me questions or comments on Arti, the demonstration sites, etc.

-r