http://en.wikipedia.org/wiki/Anti-abortion_violence

I do agree that the "holy war to end holy wars" phrase was hyperbolic, but it's also hyperbolic to expect no objection from religious people. When Stross first addresses the issue, he says:

However, if it becomes plausible in the near future we can expect extensive theological arguments over it. If you thought the abortion debate was heated, wait until you have people trying to become immortal via the wire. Uploading implicitly refutes the doctrine of the existence of an immortal soul, and therefore presents a raw rebuttal to those religious doctrines that believe in a life after death. People who believe in an afterlife will go to the mattresses to maintain a belief system that tells them their dead loved ones are in heaven rather than rotting in the ground.

That's not an extreme conclusion. It's only in the "in summary" section at the end that the rhetoric really picks up.