online non-participation

I'd like to look at non-active participation (lurking and reading-only) in a little more detail. Earlier I drew an analogy between a solo-discussion and a blog. Both are technologies which allow passive interaction, but welcome contributions (comments or postings). However contributions may not eventuate indicating that visitors are satisfied with reading alone? Hence it made me wonder why only one person contributes to the instructive value of the blog/discussion whilst others despite being very involved by their reading/learning, do not. The presence of non-contributors significantly changes the dynamic because their learning needs are being met, but those of the blogger/solo-discussion-poster may not. It's also a little artificial because the blog may not be as private as it appears to the blogger, nor the discussion board as uninspiring as its number of contributions indicate.

Two articles I want to read tomorrow:

1. Participation in on-line courses – how essential is it?
2. Teaching on the Web — Exploring the Meanings of Silence

I have chosen these 2 articles because I wanted to explore whether non-active participation was an appropriate learning strategy. In an online community you would expect to find both highly participative folk who make many contributions and those who are read-only participants. If the environment is an online course then these students may consider themselves to be actively following the course and learning, despite the absence of contributions. This of course brings up questions of learning styles. It also brings up the question of whether this failure to contribute is fair to those students who do contribute, and fair to the community (online course) as a whole - because they are not adding anything to the body of knowledge? These students take, but don't contribute?