A topic can only be removed by the moderator of a thread or me. I am the only one who can move a thread. I CAN remove the redirect from the old thread as well. I tend to leave them up so people can find the relocated thread. I am in the process of cleaning up really old redirects so there aren't pages of old redirect threads clogging things up.
Please PM me whenever you feel a thread should be removed or moved, as I do sometimes miss one or two, now that we are quickly nearing 100,000 postings and 2,000 users!