Which again like many of us have been saying in the long term will be its problem especially with the reduction in ROPs. It is already evident against the GTX670 or in games with higher bandwidth or intensive AA forms. Are you 100% certain in 18 months time it will be the case?? The card has been out 5 months.
Moreover,Nvidia is only really pushing less bandwidth intensive AA NOW. I updated the GK104 threads on both here and OcUK for ages. The only reason that the big GPU card never was released is since the GK100 failed and the GK110 probably has limited quantities even now(targetted to HPC first). What do you think will happen when the GK110 is released as a top end card??
Nvidia will start pushing more intensive quality based AA methods and you will find the 256 bit bus returning to the cheaper cards. Then see the advertising showing how the new generation has X% better AA performance than the previous generation,etc.
At least with lower end cores,the GPU is likely to run out of steam first,but not with the cores found in £200+ cards.
Remember this is not the first time this has been done,and people made the same arguments with ROP limited,RAM limited and bandwidth limited "special edition" cards.
The problem after a year to two years the limitation start to be shown. I have seen this enough times over the last decade.
By then most review sites would have just gone onto the new generation emphasising how brilliant they are.