Hate to break it to you but Kepler drivers really aren't that great as is right now either. I don't even get the Nvidia/AMD drivers thing. Nvidia has just as awful a track record as AMD does on that front. How quickly have people forgotten that G80 was unusable on Vista for six months? Or that Nvidia drivers were responsible for a full 28% of all Vista crashes? Let's be real here. They both could be a lot better.
That said I imagine GK110 (if it's a gaming card) and HD8xxx will have both AMD and Nvidia fall back a little to their 'old' positions. I don't expect AMD to maintain the lead they have right now with the ghz edition but I do expect them to regain the price/perf advantage.
If Nvidia is done with large dies in GeForce cards however it's a whole new ballgame.