Fair play to the guy volunteering to get his head removed, this sort of thing takes some serious balls.
As a transhumanist, I find this both exciting and scary at the same time. If we can successfully transplant a human head, not only will it open up new techniques and technologies, but an ethical can of worms. Who's to say we can't make clones of ourselves and have our heads transplanted in the event of extreme bodily damage? Ideally, we would have the time to study the biological and psychological effects this operation would have, but as long as he is willing and can afford it - why not?
If this sort of thing works though i can imagine people in the future exploiting the hell out of it and try to live forever by just putting their head on a different body after their current one gets too old or whatever. With world population already to big people not dieing would be a serious issue and like MTSnacks said there would be a lot of other ethical issues as well and I can imagine religous people getting really angry about this.