I'm confused - several people are complaining about the lack of color selection, claiming that they want their case for aesthetic purposes. If the whole reason for the free case is a UTILITARIAN purpose, that is, to correct a design flaw, then this free case program serves that purpose.
If you want a case for AESTHETIC purposes, that is to make your iPhone look nicer/cuter/sexier/whatever, then wouldn't you be the type of person to buy one anyway, even without the antenna issue? Meaning that you are not the type of customer being targeted by the free case deal, and you weren't having any problems anyway (since you already had a case or were getting one to make your phone look nicer).
Many pages ago someone suggested an analogy to a car purchase, saying that what Apple was doing was like a car manufacturer having a door handle problem, and you go to get your blue car fixed and they only have a red handle. That's a spurious analogy. A better one would be to describe what you want as this - you bring your blue car in, they offer you a free blue handle, and you want a chrome handle and get all upset when you can't get one.
At the end of the day, it's FREE, and for many people honestly unnecessary. I tried to affect my reception with the death grip, and I did notice a drop in bars, although never to zero or one, and never to the extent that reception was affected. In my regular usage I never have any problem.
Anyway, enjoy your free case.