Apparently IF implemented some new passive spam protection features a couple months ago.
I don't know exactly how it works, but it seems to have really cut down on the number of spam-bot registrations.

Hopefully now it will be easier for legitimate users to make new accounts without us having to deal with any spam.

Well, whatever they did appears to be kicking ass.

I can't help but wonder how much complaining it took for them to do something though (Or maybe it was the bandwidth leeching, lol).

I had changed all registrations to require manual approval, rather than just email validation.
I didn't even know that they had added any new spam protection until yesterday, so I checked the list of validating members (people who had tried to register but not been approved yet) and there was only one attempt from the last few months, as opposed to the 500-1000 we've been seeing in the last year or so.

It took them long enough, but it looks like they got a pretty good system in place now.