I'm not for it but I'm not against it.
From the ever wise words of my Rabbi;
"If we enforce Capital Punishment, either way the murderer will usually die a much more merciful death than what they did to the victim."
All of these new execution devices are always trying to come up with new ways to be "painless" and "humane" when really all they do is make it more elaborate and/or expensive and in some cases more painful for the victim, which most people would want on a murderer. A fireing squad could miss or make the person in more pain, the Electric chair fries a person's brain, hanging could choke someone to death or decapitate them, lethal injection doesn't even meet the standards of putting down animals, and all of those include a lot of pain.
Ironically though, the (and this is from my Rabbi again, he's pretty reformed I think is the word) The Guilotine [http://en.wikipedia.org/wiki/Guillotine] is probably the most "human"/"painless" form of execution. I'm not saying it should be implemented as an execution device again, but it is quick, effective, efficient, probably cheap to make, and the person doesn't feel a thing. Just a quick slice of the head and the person's dead. That's "humane", right? Letting the person die with as little pain as possible?
But all of it is for naught, as either way "the murderer will usually die a much more merciful death than what they did to the victim."
And if an innocent is killed, sue. It's amazing how one's life is retributive(?) to a few hundred thousand dollars.
But like I said, I'm not for or against it. I can see the reason to have it and to not have it, so I'm on the fence.
EDIT: And then we get to the whole "head is alive a few seconds after decapitation". The person could be put to sleep when it happens? That's even more humane, isn't it?