10/31/2018
is about to be released and it seems promising for the user and a pain in the butt for the web-admin.
The short version is there is no longer the "check the box to verify you're not a robot" as there is background tracking and an AI which is great but if you're a web-admin you have to enable a bunch of settings for it to take effect.
The new reCAPTCHA system does away with user interaction, instead using tracking features to assign a risk score to users.