Actually, all hyperbole aside, my thoughts were "why are they stopping this and why aren't WE in the US doing this?"
It seems like, if you're going to kill people anyway, that there shouldn't be a problem with this. The problem is, are you really going to kill the people anyway? Sure, it might start out that way. Pretty soon though, appeals for prisoners awaiting execution are going to be influenced by arguments that their organs could be saving lives. Same for the criminal trials in the first place. Same with the laws and mandatory criminal penalties, etc. It wouldn't take long for it to become like traffic tickets or civil forfeiture which virtually no-one can argue aren't abused to boost revenues. I was about to write that with prisoner organs it would be a matter of saving lives rather than revenues, then I realized that it's not as if they would just give these organs away, so it would be a matter of revenues after all.
Frankly I don't think it would be too long before people with compatibility factors for rich and politically powerful people in need of transplant organs would find themselves being railroaded off to prison on capital charges.