One of the key feature in the new iPad is the high speed 4G LTE wireless. If you’re an international customers looking to buy the new iPad for the 4G, then it pays to confirm with you telco if the new iPad is compatible with their LTE network.
Similar to GSM, depending on deployment and market, different LTE network operates at varying frequency band. For example AT&T’s LTE network in US is operating at 700MHz and 2100MHz bands. While some telcos in Europe and Asia are using the 800MHz, 1800MHz and 2600MHz bands. The new iPad does not have a switching world LTE thus the iPad you bought from AT&T in the US will not work in Europe telcos using different frequency bands.
Apple in its official specifications only stated LTE compatibility with AT&T, Verizon in the US and Bell, Rogers and Telus in Canada. Apple has confirmed with The Verge that “iPads sold internationally will be able to connect to AT&Ts LTE network when in the US with the appropriate SIM and plan.” Which suggests that Apple will ship the same AT&T version of iPads to international markets. If this is true then it is likely that the new iPad is not compatible with a number of LTE networks in Europe and Asia.