This document discusses the idea of virtual communities through three metaphors. It includes an excerpt from an email discussing how a blogroll enables finding blogs the author reads while also showing affinity for those included. The email notes disagreement is possible but objectionable views would exclude inclusion. A second excerpt discusses using Facebook primarily for social reasons among "friends" who are often politically like-minded, allowing some discussion.

1. Three metaphors
and a community
exploring the idea of
“virtual community”

2. Greater Surbiton
http://greatersurbiton.wordpress.com/

9. The blogroll enables me to find easily
the blogs I read, but it also shows with
whom I feel an affinity, and with whom I
wish to associate. I don't necessarily
share the views of those on my blogroll,
but I wouldn't include any blog whose
views I found objectionable, even if they
were interesting.
Email from Marko Hoare.

14. I do have an extensive presence on the
web. […] Facebook is, for me, primarily a
social thing; my Facebook profile is, of
course, only readable by 'friends',
though a lot of my Facebook friends are
kindred spirits of the Eustonite left, and
we do sometimes have discussions.
Email from Marko Hoare.