It'll be interesting to see how this is accepted by the community at large. I think explicit opt-in, combined with having the discussion about which metrics to collect in public, would be enough assurance for most that this isn't a bad idea - but doesn't neccesarily mean that most will opt-in as a result.
That they made it opt-in means that I will no longer completely rule out using golang. I don't know if I'd actually opt in, though. I haven't evaluated that issue.
