Yeah, we were surprised too. But before Captcha we had thousands of bots in almost no time. Afterwards basically zero. A few got through, but they looked manual and never posted. We cull heavily, so the rolls remain small while the number of accounts made over time are much higher. We've had probably 10,000 accounts actually created. Maybe less, but many thousands for sure (I manually deleted nearly 4,000 of them personally almost two full years ago.) We delete all the time, but now it is "as they are created." The mods get a message that an account is created and if it is obviously a bot or spammer, they get deleted within a few minutes.
The ones I see most commonly are "London escort agencies."