I have a blog that gets the usual spam, which Akismet is pretty good with. Not good enough for me to turn off moderation just yet. I am wondering is there a way to "whitelist" a list of readers so their comments can skip moderation and just get posted?
An administrator must always approve the comment
Comment author must have a previously approved comment
This way comments from people (identified by combination of name, email and site) who have previously approved comments will not require moderation. Rest of comments will.
I find it better to use a different combination
WP Spam Free - stops most automated spam hxxp://www.polepositionmarketing.com/library/wp-spamfree/
Moderate first time commenters - stops first time human spammers
For the odd person who has a problem with WP Spam Free (so far 2 people from 1000s) I also have a backup plan http://wordpress.org/extend/plugins/comment-whitelist/
I also blacklist spam pingback domains so I don't get to see their pingbacks, and on rare occasions I also do the same with an email address or IP addresses - for instance recently there was a whole datacenter with multiple servers having a conversations with themselves, so I just blocked based on the first 2 numbers in the IP address which were common to the servers and I made sure were assigned to the one datacenter.