This paper reminds me of the Barcellini et al., (2005) paper on analysis of the Python mailing lists postings. The authors don't really draw any conclusions and some of their graphs are a little difficult to interpret. However there are some interesting approaches with connect with my own analysis of evolving vocabulary use in the disCourse system. Figure 8 above shows the results of a principle components analysis on the subjects of the mail posting and presents how the topics have changed over time. An interesting approach, but it seems odd that the most consistently active components are not labelled with text in the diagram; making it unclear what we can actually draw from this representation.
Another interesting look in the data can be seen in this next image where the vocabulary terms used are broken up by the different types of user in the system. Again the graph is a little difficult to interpret, and no clear conclusions can be drawn. The authors suggest that this approach might be used to identify the roles of users within the community, which is an interesting idea but needs to be fleshed out a little further. The results of some effective means of classification could feed into Nabeth and Roda's autonomous agents approach, but it still seems to me that the best first step is to feed information like this back to the community ...
Overall an interesting paper in that it presents a number of different ways of analyzing mail list postings. The authors suggest that much analysis has been focused on code, and that there is need for more focus on social-technical systems; although since that has been the focus of my own lit review, it seems like the author's might well benefit from reviewing the last 10 years proceedings of the HICSS persistent conversations workshop which has lots of this kind of stuff. The fact that the authors don't reference seminal work like that of Sacks and Marc Smith from Microsoft research indicates that there is lots more literature they could connect with.
I ran their references through my scholar system, but only grabbed 9 of 14 possible refs, which was disappointing. Partly due to inconsistent formatting. Also some of the references switch to initial before surname after the first author; and trying to fix that I ran into ruby regex stack overflow errors. That said I have increased the precision of my title regex and I have set it up so that the title is now linked to the paper ref from Google Scholar, which is more intuitive - clicking on the title takes you to the paper itself, e.g. in ACM Portal or IEEE Xplore, or even the PDF if available, and clicking on Cited by X takes you to the Google Scholar citation list. Of course mucking around with the regex is a terribly time sync. My latest thoughts are the need to explicitly describe the different citation formats and re-build the regex thinking of them explicitly.
Cited by 4 [ATGSATOP]
 Aoki, A., Hayashi, K., Kishida, K., Nakakoji, K., Nisinaka, Y., Reeves, B., Takashima, A., Yamamoto, Y., A
Case Study of the Evolution of Jun: an Object-Oriented Open-Source 3D Multimedia Library, (Cited by 42) Proceedings of International Conference on Software Engineering (ICSE2001), Toronto, CA., IEEE Computer Society, Los
Alamos, CA., pp.524-533, May, 2001.
 Butler, B.S., Membership Size, Communication Activity,
and Sustainability: A Resource-Based Model of Online Social Structures, Information Systems Research, (Cited by 184) v.12 n.4,p.346-362, December 2001.
 Butler, B., Sproull, L., Kiesler, S., Kraut, R. . Community effort in online groups: Who does the work and why? In Leadership at a distance, Weisband, S., Atwater, L. (Eds.), Laurence Erlbaum, 2005 (forthcoming).
 Cosley, D., Frankowski, D., Kiesler, S., Terveen, L, Riedl, J., How Oversight Improves Member-Maintained Communities, (Cited by 32) Proceedings of CHI 2005, pp.11-20, ACM Press, 2005.
 Giaccardi, E., Fogli, D., Beyond Usability Evaluation in Meta-Design: A Socio-Technical Perspective, IJHCS, (Cited by 4) (submitted).
 Hippel, E.v., von Krogh, G.v., Open Source Software and the "Private-Collective" Innovation Model: Issues for Organization Science, Organization Science, Vol (Cited by 13).14, No.2, pp.209-223, March-April, 2003.
 Lakhani., K.R., Hippel, E.v. , How open source software works free user-to-user assistance (Cited by 524). Research Policy, Special Issue on Open Source Software Development, 32, pp. 923- 943, 2003.
 Ling, K., Beenen, G., Ludford, P., Wang, X., Chang, K., Cosley, D., Frankowski, D., Terveen, L., Rashid, A. M., Resnick, P., and Kraut, R. Using social psychology to motivate contributions to online communities (Cited by 173). Journal of Computer-Mediated Communication, Vol.10, No.4, 2005.
 Nakakoji, K., Y. Yamamoto, Y. Nishinaka, K. Kishida, and Y. Ye., Evolution Patterns of Open-Source Software Systems and Communities, Proceedings of International Workshop on Principles of Software Evolution (IWPSE 2002), pp.76-85, 2002.
 Nakakoji, K., Takashima, A., Yamamoto, Y., Cognitive Effects of Animated Visualization in Exploratory Visual Data Analysis, Information Visualisation 2001, IEEE Computer Society, Los Alamos, CA (Cited by 4)., pp.77-84, July, 2001.
 Pangaro, P., Participative systems. Manuscript, 2000, Available at: http://www.pangaro.com/.
 Preece, J and Krichmar, D. M. Online communities. Jacko, J. and Sears, A. (Eds.) The Human-Computer Interaction Handbook: Fundamentals, Evolving Technologies and Emerging Applications, pp.596-620, Lawrence-Erlbaum, 2003.
 SourceForge, http://sourceforge.net/
 Ye, Y., Kishida. K., Toward an Understanding of the Motivation of Open Source Software Developers, Proceedings of 2003 International Conference on Software Engineering (ICSE2003), Portland, Oregon, pp. 419-429, May 3-10, 2003.
 Ye, Y., Nakakoji, K., Yamamoto, Y., Kishida, K., The Co-Evolution of Systems and Communities in Free and Open Source Software Development, in Free (Cited by 24)/Open Source Software Development, S. Koch (Ed.), Chap.3, pp.59-82, Idea Group Publishing, Hershey, PA., 2004