It seems the patch does not fix the autogen bug. It did not for me, and I saw a couple of posts on the "other" site reporting the same thing.
What are your findings? If you start from a densely populated scenery area, and slew "backwards" away from that, does the framerate remain high, or does it drop to about 10 FPS? If it does drop, what happens if you rename your default.xml file to default.xml.bad and set TERRAIN_USE_VECTOR_OBJECTS=0 in your FS9.cfg file and repeat the test?
Starting from KPDX and slewing backwards south, I started at about 30 FPS and as I moved backwards it dropped to 10 FPS. After disabling the vector objects and default.xml, I got a steady 35-40 FPS.
Going to try it on a clean install on my laptop but I doubt it will be any different - looks like MS failed to deliver.
On the other hand, the 19m mesh support now works properly - noticed a sublte but very noticable improvement over the VFR Terrain and Switzerland Pro sceneries.