In flat spacetime, there isn't any problem with wave function collapse. I think that's the "textbook" position, although the only citation I have off the top of my head is the discussion in http://arxiv.org/abs/0706.1232 (section 1.1). How about in curved spacetime (working in the regime where localized qubits are possible)? I found http://arxiv.org/abs/1108.3896 (section 8.2.2 and 9.2) which discusses the issue a little, and there seems to be no problem with wave function collapse. Is this a consensus position?