Looking at the Akismet stats page, you can see that 90% of the comments filtered through Akismet since it started have been spam. More alarming than that is seeing the daily numbers showing about 95% of the comments as spam. That jives pretty well with what I’ve seen on my blog. Since October 25, 2005 (when I first installed Akismet) I’ve received 483 “good” comments and Akismet has trapped 2,901 pieces of spam. That comes out to about 85.7% spam (thank god my email account doesn’t get that ratio of ham to spam). I had Akismet disabled for a little bit in October and November, so I likely had more spam in that timeframe, but you get the gist.
Anyway, it just goes to show how much more crap I’d be cleaning out of my comments system if not for Akismet.