I reset the activity log for this site on the 1st November and I've just imported it into MS Word.
The log contains 2,564 entries. Of this 2,252 are instances of MT Blacklist denying a comment spam entry and 43 are throttled attempts at repeated access from IP addresses. That's an average of 75 comments per day or 3 every hour. All unsuccesful.
I'd post some of the originating IP addresses but the chances are that they're spoofed anyway.
What I don't understand is why most of the comment spam that actually makes it through contains URLs that aren't live.