Why would one shoot strictly for equivalence? FF gives you the option for shallow DOF and faster shutter speed. Given a trade between faster shutter speed and shallower DOF versus not getting the shot due to blur, I'd choose faster shutter speed and shallower DOF. I'd rather shoot a 5DII at ISO 3200 in a dark auditorium rather than a 7D at ISO 3200. The same lenses will also result in higher resolution (lp per image height) on a larger sensor.
I'm only using equivalence for comparison purposes, saying that in like for like output conditions, the 7D has the slight edge in theory (in practice, it is not really significant). BUT I also say if you do need to operate in the area that the 5D2 brings in which is not easily attainable on the 7D, obviously that's a benefit too. For those reasons, I have both cameras myself.
Personally, for a lot of my shooting, I don't need a shallow DoF and in fact I struggle to keep enough DoF on subjects. So overall, the 7D (or any other Canon 18MP crop sensor body) is better suited to me than a 5D2 is maybe 99% of the time. But I still got the 5D2 for that 1% of the time when the 7D reaches its sensor size limits.
As a parallel to the so called MP wars, I think too many people blindly think bigger sensor must always be better, without understanding why it might or might not be.