NMJH - I know exactly what you mean. 4G Providers don't use the same frequency in Australia as in America.
The frequency the Americans use won't be available by our government until after 2015. So the 4G chipset in the iPad isn't compatible with our biggest 4G Provider Telstra.
A large number of European and Asian country's are going to be going with the same frequency that Telstra in Australia use. So the 4G won't work in those countries also.
Where I work was about to purchase them for all our staff because of the 4G, as we all use 4G USB dongles on our MacBooks now.
But that has been put on the back burner now.
Maybe they will update the chipset in the 2013 iPad!!