Exponential incease in "StopForumSpam" registrations

Within the past few months I have noticed a marked increase in registrations caught by "StopForumSpam" and was wondering if any eose has experiences this? I have my registrations set up such that even after validating email I still have to approve the account. Lately I have been getting a ton of (I'm guessing) bot registrations. Usually it is either the IP address or email or often both that get tagged by StopForumSpam.

Has anyone else noticed a big increase in these kinds of bot...