Flew around Altis for a bit after today's (9-9-2013) update. The issue is still present but it seemed like it was better than it was. I flew around with the buzzard for probably a good 10 minutes starting at the main airfield. Flew to Kavala and then flew back east across the bay and the <1 fps began south of the salt lakes. View distance was set to about 3.5km and visual settings on high.

Before the fps tanked I was averaging about 40fps on those settings with occasional directional specific stuttering. Most of the stuttering cleared up though.

Also loaded again and drove down the main road through Kavala and the game dropped to <1 fps after a minute or so.

Has this been looked into any more?

This issue is resolved for me as of today's dev branch update (September 18th)

EDIT: Nevermind, but it is a rarer occurence than it was before.

I am having the same issue as well. My DxDiag is uploaded. Running a 32 bit system.

AMD Phenom II B50 (4 core) 3.1GHz
4GB Ram
GeForce GTX 650 Ti Boost