Im glad to report that:

[David198502]

for me unfortunately the stutters increased much since the last official patch.
with the beta patch i could fly over london almost smooth and only minor stutters.now the screen freezes for 5-10seconds(and not only once).its unplayable again.luthiers suggestion,to set buildings detail to high or lower doesnt help either.
i have squares of green and brown all over the map.fps dropped from average 50 to 40 over land.if i want to quit a mission and hit escape,i will see windows desktop(i have to push it about 30times until i see the clod interface again).and all that after a fresh install of the game and with the latest drivers and steam cloud on as suggested by luthier.im pissed