Notice the small amount of frost damage. Yes, it did frost the night of Thunder over Louisville (4-17-10).
The photo on the left shows development in all stages. Some flowers are closed, some open and a few have been pollinated. You can notice 3 (four if you count the one on the left) stigmas attached to the blueberry in the callyx cup stage. The photo on the right shows blueberries in callyx cup stage but most of the stigmas have fallen off. Some frost damage is apparent but it is not significant.