After some reading and drawing information from several sources (thanks Jackie!) I've settled on a plan that I hope works. And if it doesn't then I'll try something else.
I'm pretty sure that the treadmill and MFP are overestimating the calories I'm burning while running. And further, I want my workouts to help create that calorie deficit that's going to cause me to lose weight. I'm pretty sure that replacing my calories burned during a run, calorie for calorie isn't an effective way to lose weight--especially if my workout calories are overestimated!
Currently on non-gym days I'm consuming between 1500 and 1600 calories/day. This is what's helped me drop the 28lbs you see over there in the sidebar. Since it's working, I'm going to continue that. On run days however, I'm going to cap my calorie intake between 1700 and 1800. This way I'll be getting extra calories to help fuel my runs, but won't be over eating either.
It's interesting the choices I find myself making while I'm restricting calories. I try to eat nutritionally dense foods, and I keep an eye on the nutrients that MFP tracks. When I only have a certain number of calories to eat per day, I make choices based on how much of my calorie budget it's going to cost me. Almost always if a food is too "expensive" and not a good value of calories vs. nutrients, the choice to avoid it is also a nutritionally sound choice. For example, there's no way I'm going waste 240 of my allotted calories on a soda. I mean that's nearly a 1/6th of my daily calories! For the same 240 calories I can eat 6 oz. of greek yogurt, a plum (yum!) and a slice of my favorite cheese.
I think the key to long term weight loss and management lies in listening to your body and learning what's truly hunger, what's thirst, and what's boredom. I thought I was doing a good job at this, but I simply wasn't hungry during the days, and calories started to dwindle more into the 1300-1400 cal/day range. I stopped losing weight until I forced myself to eat at least 1500 cal/day.
Overall, I hope this plan continues my weight loss and allows me to push my runs as well. I can hardly wait to lose more weight, because I know that every pound I shed is one less pound to carry with me on my runs. And I can hardly wait to run, because it helps me shed those pounds!
That's the new plan.