They killed captcha support in 0.18, which basically negates one of the methods to stop the bots… so if we upgrade, we will likely need to email verification until 0.18.1 is released OR stay on 0.17.4 until 0.18.1 is released where they’ve promised to bring it back.
Looks like 0.18.1 was released yesterday and I think it re-adds captcha.