I have a customer that is planning to upgrade to the 2012 version and to upgrade their PCs around the same time. I read somewhere (I don't remember where so that is why I am here) that some FDO options are not available in the 64bit version. Is this true? Is there anything else in Map that doesn't work in the 64bit version but does work in the 32bit version? I want to move them to the 64bit version but not if they loose some functionality. They plan to use Map with their GIS to convert between AutoCAD and ArcSDE but may still need to do some work with SHP files.
I would only hesitate if you are currently run OSE (Oracle Spatial extension), otherwise you would be good to go.