Many cars prior to the F-150 have had aluminum bodies (Land and Range Rovers, for instance) that sold well. I would think that many truck drivers are more concerned with towing capacity, power and fuel economy than the specific metal the body is made from. Besides, the aluminum won't rust!
If you're buying a F-150, you are more concerned with it holding up. This is the vehicle of construction sites and farmers. It is truly the vehicle of I need to haul that stuff over there where they might not be a road. The concern is that the 2014 F-150 will not hold up and be more expensive to repair.
This is Ford's flagship vehicle. It cannot just sell well, it must put up amazing numbers. Its the iPhone of the car world.
1) the F-150's gas mileage isn't stellar, but it does even out when hauling.
I've wanted to do something like this for a while now (I was going to call it "sub rosa linux"). Little linux machines that would try to stay connected to any network they could attach to and be as undetectable as possible. While I like the idea from a geekery point of view, I'm not sure what the real, legal uses would be.