Having just completed a trade transaction in the market place, I instantly thought of another forum I am a member of that uses the Trader plugin. I think it would benefit everyone on the site in the long and short term as you would no longer have to do a search on the persons name to get a quick idea of their feedback/rating on here. It would allow users to "rate" transactions, so if someones a scammer they will more than likely have a negative rating, ect. http://www.simplemachines.org/community/index.php?topic=98912.0
Just a thought!