UPDATE: I crashed again a few hours after posting this, rebooted and crashed almost immediately after loading the game again... sigh... it plays good for a while sometimes. Sorry if I got anyone's hopes up.
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I stumbled on a post in the steam users' forums where someone had mentioned that reducing their system memory to 4GB solved their crash problems, so I decided to give it a try.

I had 8GB installed (2x 4GB) so I powered off my machine, and removed two of the four memory modules, rebooted and launched the game.

I've been playing with 4GB of RAM for 2-3 hours and no crash so far (knock on wood)