Supreme Court rules that death penalty is "cruel and unusual" for man who raped a child

This isn't a joke (since I posted a joke story yesterday about the Supreme Court and the death penalty). Fascinating decision. At first you'd like to say, of course it's appropriate to kill someone who rapes a child. But then, this decision forces you to think of when the death penalty is appropriate. What rules would you use? Normally, I'd think that the death penalty is only used when someone kills someone else. But is rape so unique a crime, and raping a child so unique a victim, that in this case an exception should be made? Thoughts? Oh, and the decision was 5-4, again. Meaning, McCain changes everything.