Combine all ingredients (except brie) in a large saucepan. Bring to a boil over medium heat, and cook 2 minutes. Remove cinnamon stick. Cover and chill blueberry mixture until ready to use (or let sit, covered, at room temperature for up to one hour).
Preheat oven to 350℉.
Place brie round on baking sheet or in a baking dish. With a sharp knife, cut through rind around the top edge of the brie (just make a cut into the top layer of the brie all the way around, but don't remove it). Bake 15 minutes, or until cheese is soft and melted. Carefully move hot brie to a serving plate. With a sharp knife, carefully cut under the top of the brie (under the rind) and remove. Top the brie with the blueberry mixture, and serve with baguette slices or crackers.
Notes
*If chilling the blueberry mixture, be sure to take it out of the refrigerator and let it lose some of its chill before placing it onto the hot brie.