Melt the butter and set aside to cool.
Sift together flours, cornmeal, baking powder, baking soda, and salt in a medium bowl.
In a large bowl, beat together milk, sugar, eggs, and vanilla until foamy.
Stir in flour mixture, then add melted butter.
Let rest for 30-40 minutes.
Preheat waffle iron.
Stir blueberries into batter. (It's OK if a few of the berries get crushed.)
Cook waffles according to iron's instructions, making sure to spray the plates before each waffle.
Serve immediately with the best butter and maple syrup you have.
Store any leftovers in the fridge, and crisp up in a 350°F oven.