What happens when you move a thread

I have a new "In The News" forum on our site, and we have been adding current and news worthy postings here and then featuring this news article for a day or so depending on the replies it gets.

What happens when we move the tread into another forum area down the road. Does this action mess up my SEO? Are search engines having trouble finding it? I know search engines already indexed the posting, am I confusing the search engines by doing this.