On 14 Aug 2006 19:56:58 -0700, "Andrew Sarangan"
wrote in . com:

for the vast majority of these groups anyone can join just by sending an email to
majordomo.

There is are differences between groups that require its members to
join, and Usenet. The group moderator has the ability to oust what
s/he considers "disruptive" members at the expense of limited
exposure.