I just had two quick test runs with the new patch, 2xHurri against 5 twin bombers. Over all, fps have increased by about 15, with higher fps when flying alone. Stuttering, especially over land, hasn't improved much.
This game finally feels playable for me
1440x900
AMD Phenom X4 9500
Sapphire HD4870 vapor x 1GB
3 GB RAM
Model detail: med
Building detail : very low
Land detail: low
Visual effects: medium
Damage decals: medium
Building amount: low
Land shadow: low
Grass: off / Shadows: on / Roads: off