I am the founder of the largest community website for the opensource 3d software Blender (www.blender3d.org).
This community (www.elYsiun.com) is largely based around the forum (phpBB 2.0.x). For a while now we’ve been looking into expanding elYsiun into a full community website, attempts at this have been made but due to lack of time and motivation they have never quite been finished.
Now we’re looking very seriously into using an existing opensource php / mysql based CMS, Drupal sure does look to be a very interesting and powerfull implementation. There are however some things we definitely need / want on elYsiun. Two of those things can potentially break the decision to go with Drupal, or any CMS for that matter.
1. The forum
We currently use phpBB as the backbone of elYsiun and I for one would like to keep it that way, or include a forum which atleast comes close to the feature set and usability of phpBB.
2. An article system
Like I said elYsiun.com is a community website for the opensource 3d software Blender. Blender has a very extensive feature set which results in a fairly high learing curve (as with any powerfull 3d software). Over the years experienced users have created hundreds of tutorials for Blender, some very small and some very extensive.
These tutorials tend to be texts explaining how to attack certain problems, illustrated with images and downloads.