I notice I don't see anyone with the contributor group, and it appears to be come from the group membership in the UCP. Is it gone for good, if not, are there any plans for implementation of it in the future (perhaps once these forums are upgraded to 1.8)?
I'm sure it's not gone, there are still several people with this rank:
I don't know whether and why the applications were closed, though.
Applications to the contributors group are closed. We only invite members we feel are contributing to the group. See
Getting Involved: Contributors blog post for more details.