my wife is currently in California assessing the various iPad options,
Not sure about the land of uncle sam, but certainly in Europe,
ALL Apple products are now sold
unlocked and you do not have to specify any carrier at the time of purchase (I recently purchased an iPad with 3G, the 3G being their "just incase", I don't use it and don't have any SIM card at present).
I thought they removed locking worldwide a few years ago, but I guess it might remain in the US ? I'll do some searching and see if I can come up with anything....
Also - she can't expect to use the cellular option in New Zealand, or maybe any other Country by just buying a local SIM card because although New Zealand has 3G capability the frequencies used in the Asia Pacific region are different to the 3G frequencies in USA/Europe etc. ??
As far as I know.... that is bull.
I'm fairly certain Apple products use one chipset design per product. You get global coverage.
I have certainly used European Apple products in AU/NZ/Asia on local SIM cards without issues.
The Apple spec sheets are publicly available, you can check for yourself what RF frequencies are covered.... I'm fairly certain you'll find its worldwide.