I posted a link to a different article on the same concept not too long ago.
Yes, a calorie is a unit of energy. But caloric availability from food isn't that clear cut, nor is each individual body's utilization of that energy.
I don't believe that scientific knowledge about this is currently sufficient for anyone to modify their diet over it, but I think that continuing research will end up helping develop more effective treatments for obesity.
It took me a really long time to discover and accept how my body reacts to sugar and simple carbohydrates. It would have been a lot easier to have known that information a long time ago and developed a personal eating plan based on it.
I think that ultimately, people will be able to get detailed and specific information about their personal metabolism in a way that helps them optimize diet and activity to maintain good health.