So have you noticed that spam comes in waves? I can go for weeks and not get any, and then in the span of 48 hours get hit a few dozen times. Fortunately I have no problem taking the 10 seconds needed to add folks to the MT-Blacklist file so that they can’t do it anymore, but you’d think they’d give up.
For all you bloggers out there that use an older version of Movable Type and DON’T have MT-Blacklist, may I recommend you use it? It’s effective and for each person that employs it that’s one more spammer that may give up because it’s not worth his time to post when it gets deleted within hours (and sometimes even minutes if I happen to see it throughout my workday).