I posted this on the thread above on international plans and I will post it here on this thread.
I just went to the Apple Store to check this all out. The Apple tech person told me that the system is open. So you will not be moving micro chips around. Instead, you will cancel your AT&T plan before traveling and when you get to your travel destination, just click on settings and the iPad will tell you which national companies there offer a monthly plan. You can choose one, see what their rates are, and if your like the rates which are based on national rates and not huge AT&T international roaming rates and huge per minute charges, you can then just click on the monthly rate and company you like and you are in. No looking for stores to find microchips and swapping out chips.
This looks great and is far better and easier than I thought it would be.
Mike Ruggeri