Yet there are many people in the real world, both hospital administrators and especially voters, who would support the other decision - the one where we give one person useless care now but let ten potentially curable people die later - with all their hearts. Our first job is to spread enough consequentialism to get people to stop doing this sort of thing. After that, we can argue about the technical details all we want. We can stop shooting ourselves in the foot even before we have a complete theory of ballistics.
There should be a top-level post to this effect. It belongs as part of the standard introduction to rationality.
Here is a related post: http://lesswrong.com/lw/65/money_the_unit_of_caring/ I'm sure there are others.
I just came across an essay David Friedman posted last Monday The Ambiguity of Utility that presents one of the problems I have with using utilities as the foundation of some "rational" morality.