From the forums: http://forums.atlassian.com/thread.jspa?forumID=96&threadID=6876

"We have started a page which became a general repository for comments, using the [duh] Comment feature. But now things have gotten a bit out of hand, and we would like to go back and create a decent page hierarchy, by moving each set of original posts, along with their attendant comments, to a new page."

One useful refactoring would be to promote a comment so that it becomes its own page - and any comments under that in the thread become comments on the new page.