I care, or at least i care (A LOT) about my idle power consumption, and if Fermi pulls twice as much power idle than HD5800 its a no brainier for me, regardless of performance difference.

And im a bit confused about the ECC. One moment you use it as a feature to hype both Quadro and GeForce and the next you say it will make no difference if GeForce has it or not (which it wont).
Im getting the impression that nvidia is pulling out a lot of technology that looks good on paper, but might not be that usefull IRL, or at least in gaming, which must be the biggest high end GFX market.