You are correct. Intel Centrino Duo can have either the IntelGM/PM965 or Intel 945 Chipsets. Intel Centrino Pro systems have the Intel GM/PM965 chipsets. If you are shopping for a Centrino system that supports vPro, it must have the "Pro" branding, otherwise it will not support Intel Active Management Technology (AMT would have been disabled by the OEM on an IntelCentrino Duo branded mobile platform.
I hope this helps.