They want everyone to get the 580 that really wanted it before bringing this guy out. It will probably have awesome performance and OC ability like the 470 before it. But they want to get it on the street before the 6900's. That would be the good move.
If everything goes as planned, the 570 wont really beat the 69xx by a margin of time that would really give it the leg up. But it might be a fantastic overclocker. I wonder what that says about the 560. The 560 was clocked low and could OC very high, but when it did, it overlapped with the 470 a lot. If this is also clocked low, i wonder if that frowns upon the 560 being as good a performer as we had hoped, otherwise they likely would have clocked it higher to avoid overlap.