Derek Powazek's Design for Community was a very thought-provoking book; many of the ideas in DrProject had their origins in it (the rest came from Jon Udell's Practical Internet Groupware, and from SourceForge). There's now a recording of a presentation he gave in March on the web; it's a little Web 2.0-ish, but well worth listening to, particularly as we're thinking about adding tag clouds and human-generated blogs to DrProject.