Depends on a few variables...Time frame for launching, ease of integration, etc, etc. Ignoring those... As a user of OpenID I would vote for enabling before go

Depends on a few variables...Time frame for launching, ease of integration, etc, etc. Ignoring those... As a user of OpenID I would vote for enabling before going live (one less new account to create). I have typically noticed its the legacy sites (pre OpenID) that are integrating, whereas most new services looking to leverage the service have it ready for go-live.