Prepare ganache: 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.