I think I am in the same boat. The more I dwell on things like this, the more I want a full frame. It is interesting to line up the upper end bodys (at least in Canon). The 1Ds Mark III is a full frame sensor, but the 1D Mark IV is a crop sensor. I assume they will come out with a 1Ds Mark IV, but who knows. It must be annoying trying to find the perfect body when it seems every single one of them sacrifices at least something. You would think they would make a pro model that has it all.