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Nope, not a BTO option. Can't be installed afterwards because it's soldered onto the motherboard.
 
Not to hijack but since the OP's question has already been answered...

What kind of performance boost are we looking at from a 6970M to a 7970M (rumored to be in BTO iMac)? 50%?
 
Nope, not a BTO option. Can't be installed afterwards because it's soldered onto the motherboard.

They aren't soldered onto the motherboard. The GPU is on a separate MXM board and technically can be replaced. Don't think it has been done though. There are several threads here discussing it and someone wanted to try.
 
Not to hijack but since the OP's question has already been answered...

What kind of performance boost are we looking at from a 6970M to a 7970M (rumored to be in BTO iMac)? 50%?

Benchmarks are out.. linked in another thread. Up to 100% depending on how you measure.
 
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