You would have the option to run your memory asynchronously, ala 133/166. As to the benefit of this I don't think it will be much. It does however open up some interesting options if you mod your chip and run it at 166/166. I am curious to see what ECS has learned from there hugely succesful k7s5a and if they improve withthe next board. However, ECS will not be the only player this time around, Epox among others also have boards with this chipset in the works.
It's not what they tell you, its what they don't tell you!