A picture says more than thousand words; here is my current stats regarding WordPress-comment-spam on this site.
Going from 9700 spam in October to 17 in November is pretty awesome.
There aren’t many people that leaves comments on the site, but this reduction actually makes the site work faster.
I haven’t read about any spammers been caught nor that Akismet have upgraded their detection routines, if anybody know please let me know!
