Yes, this entire scenario is based around scenarios where there is benefit to cooperation. In the edge case where such benefit is '0 expected utilons' the behavior of the agents will, unsurprisingly, not be changed at all by the considerations we are talking about.
So I should interpret Will's "Omega = objective morality" comment as meaning "sufficiently wise agents sometimes cooperate, when cooperation is the best way to achieve their ends"? I don't think so.
Here's the new thread for posting quotes, with the usual rules: