Based on Kael's latest post, it appears that there will only be one more beta so I wanted to make sure I reported a few things that I haven't seen addressed. I am using Win7 64bit with 8GB of memory on a new Ivy Bridge rig (GTX 670 graphics card).
I've been playing .983 quite a bit and noticed that if you reload from a save several times things start to get weird with the graphics. Several times I've had the green unit outline go away after reloading a few times. I've also had the terrain numbers and icons denoting squares that can be settled go away. This all fixed if you exit the game, restart the game and then load from there. It appears that the reload code is not freeing up all the resources that it should or not reloading them properly when done within the game. Since this stuff starts happening after only a few reloads, I hope you can get it more stable before release. This is something folks are sure to notice.
The second issue I noticed happens when an enemy army ends their turn on top of a caravan. When that happens and you try to attack the enemy unit, you cannot. The dialog combat screen comes up but the option for tactical combat is disabled (greyed out). If you choose the remaining Auto-combat option, then the game freezes with your attacking army running in place toward the enemy unit square. This happened multiple times when I reloaded from an earlier turn and tried attacking from different positions. Finally I exited the game entirely, restarted the game and loaded the save and then it finally let me attack the enemy army.
I haven't had the game crash on me at all since I bought my new Win7 64 rig but I am still seeing a lot of these little unstable glitches related to reloads. Maybe there are still threading issues leading to some of this stuff, I don't know. I just hope the final release improves it.