As some of you might have noticed, the comment/trackback spam is currently improving again. The spamblock plugin currently can catch a lot of spam, but had a slight weakness in terms of processing the ruleset.
Usually, the spamblock plugin walks all MODERATE/REJECT rules, and aborts that checking once the first rule hits on a mail. Recently it showed up that most spam is set to "MODERATE" even before some more aggressive spam detection rules were executed, so you might have received Moderation-Emails quite often for emails that would have been marked as spam later in the ruleset execution flow.
The latest version 1.40 of the spamblock plugin (Download here) will now also perform any other rule checks on a comment/trackback, even if it already had been marked as Moderate. This way, you will have the chance that another rule marks the comment as spam, and then will not infiltrate your mailbox.
Please give us feedback to tell us if this works for you, or if that new behaviour introdues any problems for you!