Place chopped bittersweet chocolate in a bowl. In a saucepan, combine soy milk and scraped vanilla bean. Bring to a boil; pour over chocolate.
Let stand 1 minute.
Remove vanilla bean and whisk until smooth. In a blender, process drained silken tofu until creamy (10 seconds).
Add ganache; blend until smooth (20-30 seconds). Spoon into 5 individual bowls; refrigerate until mousse is firm (1 hour). Before serving, divide 1/4 cup each raspberries and blueberries among bowls.