the 8800GT revolutionized the market with its price/performance values, right now i think nVidia is more focused on getting the performance crown back at any cost.
i think the real question is if nVidia can PHYSICALLY make a card stronger than the 5970.
because as we've seen (or read), the 5970 pushes the envelope in power consumption. its right there on the edge of engineering bounderies with the ATX specifications.
can nVidia make a card more powerful but more power hungry than the 5970? so power hungry that it will break ATX specifications?
if we're going to rule out anything that beats the 5970, then why wait for Fermi at all? just to get an expensive card that doesn't beat ATI's flagship? that certainly wont induce any price drops on either side.
if i was looking to buy, i'd buy ATI now and be happy with its great performance.