D. Suthers and J. Xu. Kükäkükä: An online environment for artifact-centered discourse. In Education track of the Eleventh World Wide Web Conference (WWW 2002), pages 472–480, Honolulu, HI, USA, May 7-11 2002. [url]
This paper present Kukakuka, an environment for artifact-centered discourse (ACD) that was developed by the authors following the conclusions of several studies showing that linked ACD is more efficient that other forms of collaborative annotations. The evaluation of the system reported in the paper is extremely informal but presents interesting findings. Messages collected with this system are overwhelmingly “on task” with little topic drift. Second, the focus of the discussion is maintained as much by the ability to form a new thread centered on a new artifact as it is by the restriction that all messages within a thread are displayed along with the single artifact for that thread. The ability to handle multiple artifacts within a single discussion space is critical.
The paper also contains some nice background references for ACD applications and studies pointing out problems of threaded conversations.