Once again, I'll throw in my two cents.
There are people who have those defective Wiis. And I'm pretty sure that Nintendo is giving them a fair shot at a second try. After all, who does it kill more? A person who paid $250+ for a machine that doesn't work properly, or a person who doesn't have it at all. I can bet Nintendo is taking care of the people that spent hard-earned money first.
But I have no source, no proof, just an idea that trickled down my little head, because people who don't know about this forum, simply don't ask for help. They just ask for another console without trying to fix the problem themselves.