New Invisible reCAPTCHA – any takers?

I've been playing with this one for the last few days. For the "trusted" user, there is nothing they need to do (not even that "I am not a robot" checkmark). But, if Google's engine doesn't like you, you will get stepped up to a image reCAPTCHA. Anyone have any prelim results in production on how good this thing is? Still in beta ("real" beta, not just Google's long tail beta).

On a related note, with the v2 reCAPTCHA (i.e. the current mainstream one), with due consideration to non-ideal user experience, what are you thoughts on how well it does with bot traffic?

Hopefully, this new invisible reCAPTCHA will be better.