I'm having an issue where trees/rocks/etc will vanish and re-appear in-game.
What happens is I'll move towards where I know a "tree" or "rock" or such is, and it will just appear on the screen... and say if there are multiple trees/rocks/etc there, they might all pop up.. or 1 will and then if I move a bit closer the other's will appear.
I'm not sure I'm describing this very well.. I have nothing to take video's to show.. I'll try and grab some screenshots. (see below)
I've had this problem with 3 different video cards, on 2 different systems.. so I'm sure it's not video card drivers, manufacturer or computer.. (unless it's the cpu manufacturer..)
Current System:
AMD Phenom II 965
ATI Radeon HD5870 (Sapphire Vapor-X OC'ed)
4 GB G-Skill ram
Windows 7 Ultimate 64-bit
I've had same issue on old system:
AMD X2 3600+
2 GB no-name ram
Windows XP Home
nVidia 7600GT / nVidia 7950GT (Gigabyte / XFX)
Really not sure why it's doing this

In game settings are 4x AA, max/best filtering.. tried with and without V.sync enabled, resolution is 1920&1088, post processing is on.. hmm, here's a screenie of my in-game settings..
Here's some screenshots...
Pic #1 - No flower displaying, pic #2 has a flower.. and notice how the fence gets sharper and more detailed in 2nd pic as well..
Next series demonstrates the problem a lot more. Take a look at how the tree appears, disappears, re-appears and then the other tree's appear finally..
This is bizarre.. Initially when this was happening on my old comp I just thought it was cuz my comp was a POS comp that was struggling.. but my current comp is sooo much better than my old comp and can do things sooo much better... and yet it's experiencing exactly the same issue ;/