It says forthcoming, so I'll give in to my urge to nitpick.
Page 6: Will the audience be familiar with the term "instrumental rationality?"
Possible typo on page 10: "the idea whole brain emulation," should be "the idea of whole brain emulation."
Controversial point that could be omitted on page 15: Claim that a truly desirable outcome means no conflict at all. The main point could be retained if it was changed to the less controversial claim that in a truly desirable outcome there would be no stories about saving the world against all odds.
Those are the only three things I noticed - overall, an excellent paper.
Just noticed that Less Wrong has apparently not yet linked to Bostrom & Yudkowsky's new paper for the forthcoming Cambridge Handbook of Artificial Intelligence, entitled "The Ethics of Artificial Intelligence." Enjoy.