Some new official info from ubi forums

Originally Posted by CharveL

Just so you know, or maybe forgot from the other thread, DX11 won't necessarily make the game faster anway - just prettier - when your bottleneck will be the CPU crunching all those planes and objects. It does have the potential to speed things up for simple objects like, say, terrain or water by using tesselation but you can't use it very easily for detailed objects like planes.

Thats correct but as we have seen in some of the earlier vids, its the terrain that cause's all the stutter, hence the reason for the DEV's having to take so much out of the game. Calling the game SOW Battle of Britian would of been a mistake with the amount of aircraft we can use, its more of a Channel skirmish.