Our boys did it in August 2005 and loved every second of it. The kids in the group each received pirate bandanas and were given life vests to wear. They boarded their "pirate ship" and headed out to find clues that would eventually create a map that would show where the treasure would be they were searching for. They searched the waters around the BC/YC and headed into the lagoon at Epcot. They made stops in Mexico and Canada. DH and I walked around the Boardwalk, ate some breakfast and headed into Epcot to walk around. When we were there, we saw the "pirates" land in Canada and search for their clue. They were giving everyone "aarghs" as they passed. It was so cute. They had lunch and continued their search for the booty. At the end, when they found the treasure, they each received a small treasure box full of cherished plastic pirate related pieces.
If you do a search, there was a rather lengthy post on it a few months ago with some more detailed descriptions.