It doesn't even matter. The video on the site says it all when Sam says "This guy designed the iPhone, the Macbook Pro!" -- they're buying a brand, a legend. They can now say they have "the iPod guy" on their team. Nobody else has Jony and that's what matters.
They want to tell their investors and customers that the iPod guy designed whatever magical widget it is they are building. That is worth the cost to them.
If you're designing a piece of consumer hardware, then having what the general public consider the #1 designer in the world on board is golden.
