I see this sorta thing in the realms of r`n`d. I don`t personally see the historical benefits of running cards like this, without the future thinking of getting the same tech on 1 card.
In the nVidia pov, u buy 2 x 8800 cards kick arse for a the 2nd half of a year or so (about the time it takes to get drivers anywhere near stable, and dev types to utilize em), then a single card comes along G90? that may cain it as 1 card. (oooo what a thought)
Then u`r in the realms as a buyer.. 2 x 8800 or 1 x G90 ?
Couple with that mobo manufs having issues all over the place with their design and what the cards can actually do. It all eats away at this under-a-year period in which u`r meant to reap the benefits of more than 1 card.