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Seems plausible to me with the increasing velocity of technical
and competitive developments.

You may not WANT to believe it, but it may happen anyway.
 
If this happened they would have to be very careful as to how they market it so that current iPhone 4 users didn't demand a swap. I don't think they could release a new one soon and mention the antenna at all without legal action.
No problem. They'd simply advertise it as:

Sorry, folks, iPhone 4 is a dud. Get the new iPhone 5 today*

*Be sure to call AT&T 101 times to check your early upgrade eligibility.
 
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