With release 83 yesterday, the 'Spam protection' checkbox over here now covers both comments and private messages. So the following is the FAQ draft for this feature. This would be a FAQ that is linked to from anywhere that's talking about controlling comments, comment spam, unwanted comments, etc, such as:
-- FAQ 23 - How do I control who can post comments in my journal? - Put a bullet point of "Activate the Spam Protection feature" at the bottom of the bullet point list, then remove that hastily-added last paragraph.
-- FAQ 201 - How do I mark a comment as spam? What does this option do? - Stick a line in here somewhere about "If you are receiving spam comments, go activate blah blah."
-- FAQ 109 - What should I do if I'm receiving harassing or unwanted comments?" - Same sort of thing. "If you're receiving spam, blah blah."
There may be other locations as well, but those are the obvious ones I saw.
Also note that this is intentionally non-specific as to how things are actually identified as spam. We do not want to be broadcasting what we're considering to be spam or how our systems are making determinations, etc.
NOTE: The images are just quick crappy things I did in Paint just to show "here's what images likely work here." When this is taken and put up for real, I'm sure a designer can get us better quality images than these.
Title: "How do I help protect myself from receiving spam comments and messages?"
The Spam Protection setting can be activated to help automatically identify potential spam comments and messages. Activating the feature will take the following actions for both comments and private messages; it is not possible to activate it for only one or the other.
Spam protection for comments
When Spam Protection is activated, comments posted to your journal which our system has identified as potential spam based on a variety of criteria will be automatically marked as spam and moved to a suspicious comments section. Any comments posted by users you have added as a friend will never be automatically marked as spam.
When viewing an entry with comments that have been automatically identified as spam, you will see a '[#] suspicious comments' link next to the total number of comments that have been posted to the entry.
Click the 'Read suspicious comments' link to review the potential spam comments at any time. If an individual comment is not actually spam, you can use the Not Spam button to unscreen it and move it to the main comments page.
Spam protection for messages
When Spam Protection is activated, private messages from users who have been identified as potential spammers are marked as spam and moved to a special folder in the Inbox. As with comments, you can review these messages at any time to either delete them or mark them as not spam.