The main concern should be overall caloric intake. That's what truly determines whether or not one loses or gains weight.
Oh, and the link I posted can also be used for cardio as well. The point of posting it was to show that there's a good reason for pre-workout nutrition, but that doesn't limit it to weights. Cardio should be used as a way to increase nutrient partitioning, and as a way to burn extra calories. One is better off eating more and burning it off with cardio, rather than just eating less. This will help increase RMR and, among other things, give better gains in the end.
By the by, Jdevlin, stop spreading fallacies. This bullshit about having to do it on an empty stomach is ridiculous. Take in less calories than you burn and you'll lose fat, provided you're getting adequate protein.