Is there a way to create, or is there one already, a means that would allow visitors to comment but, first validate their email address before the post is "posted" to avoid "spam"?
Is there a way to create, or is there one already, a means that would allow visitors to comment but, first validate their email address before the post is "posted" to avoid "spam"?
There is a moderation option, "Users must have previously approved comment to comment".
Settings -> Discussion.
Also: http://wpmututorials.com/how-to/stopping-spam-comments-sitewide/