Far too early to say with any certainty. Wait until the Apple Expo on March 7 and we should know for certain. My guess is that it will use an LTE SIM but should work on the 3G data network as a backup where LTE networks are unavailable.
Sorry for posting such a dumb question....
Given the rumour that iPad 3 will be compatible with 4G, then does it mean that if I insert a 3G sim card therein, i canNOT get connected to the net? or i will still be connected but performance of the device will not be at its best?
thanks.

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