I think that a large part of the actual spec choices will be contingent on the demands of the heroic encounters. It is entirely possible that the specifics of the respective strategies will favor one spec over another (for whatever reason). If you recall ToT, there were several fights where Destro was particularly good, despite being behind on simulated numbers. Something similar can probably be expected in SoO (to a degree) and is likely to directly influence the spec and stat choices of heroic progression raiders.
More data will no doubt be streaming in as soon as the patch goes live and people have a chance to see things in action. I expect the next month or so to be filled with lively debate and polarizing discussions on how to optimally spec/gear for SoO heroic.