Releasing one of these at 1300mhz or whatever is just going to kill the overclocking potential of the card.
I would choose a better binned Tahiti chip that can easily hit 1250-1300mhz HD7970 over a 925mhz 7970 where I have to play the overclocking lottery just to reach 1.25ghz. I think a product is way better if it's pushed the max from the factory rather than me having to overclock it 40% just to reach the
same performance that can be purchased from the factory for the same price. For example, if GTX460 shipped at 850mhz it would have been a much better videocard than when it was shipped at just 675mhz but the user could overclock it to 850mhz. Unless there is a large premium attached to pre-overclocked cards, why wouldn't you want a faster clocked card? If Intel sold me 2500K @ 4.5ghz from the factory, I would buy that over the 3.3ghz stock version for $20 more because it's guaranteed. In this case, it even means a better binned 7970 chip.
The whole point of overclocking is to get extra performance for free on top of already great performance, NOT to buy a card that performs lackluster at stock speeds where you have to overclock it 40% just to achieve the desired performance because the product was purposely held back from the factory (see HD7950).
Not everybody gets into overclocking. A factory overclocked card with good cooling and a warranty is good enough for alot of people. Insert card install drivers is about as far as alot of users go.
Overclocking should be a bonus, while excellent stock performance should be there to begin with, especially for premium products. It's far more impressive for a company to launch a 1200mhz card than to gimp it to 925mhz and tell gamers: Here overclock it. Premium products should have premium performance from the factory. If there is extra overclocking headroom, that's great, but it shouldn't be required to achieve.
Also, given that this will be a new stepping, it will also make 7970 OCed more competitive against after market 680s since today 1250mhz is not "easily achieved" with an air cooled 7970. I don't see why it's a bad thing that AMD is releasing a new stepping.