Place the vanilla bean and insides, water and sugar in a small saucepan and bring to a boil. Reduce heat to low and simmer until thick and syrupy. Let cool.
In a large pitcher or punch bowl, combine the juices and the syrup. Refrigerate until just ready to serve.
Just before serving, add in the champagne, sliced oranges and cranberries. Serve chilled and/or over ice!