From things I've read [1] it seems that the vast majority of people consume more calories than they 'burn' but only in some people is it converted to unwanted weight gain. The real question, as many people have been referring to, is how do you determine whether your body hangs onto the extra calories as weight or simply disposes of it.
Saying "If you eat less energy than you burn, you will lose weight" is certainly true, but is akin to saying: "If you never get in a car your chances of dying in a car accident are significantly reduced." It's true...but not really helpful or meaningful.
1 - http://www.amazon.com/Why-We-Get-Fat-About/dp/0307474259