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Maybe Apple is waiting for Sprint to build out some LTE?

Or, perhaps Sprint doesn't want to pony up more cash for their own iPad variant. Allegedly it cost them a pretty penny to get the iPhone.
 
Sprint's current 4G is WiMax which its phasing out for LTE, but Sprint's LTE isn't built out as much as ATT or VZWs. So my guess is once Sprint catches up there will be one, but not until.
 
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