Are iPad/iOS updates region dependant or serial number dependant?
AFAIK, hardware wise they are all the same (well outside of storage and 3G) it is serial number that determines some features. The serial number has a country code in it and the update process can determine which applications need to be removed. If, for example the SN country code is in the EU, the volume has to be limited and the radio has to be adjusted for differences in Wifi channels.