You'd better know what you're getting yourself into. 
 
Things to bear in mind: 
 
The game only uses one CPU core, is not optimised for dual-core, let alone quad-core, CPUs. (Bananas, I know.)
Therefore, the game is very heavily reliant on your graphics card setup. That means, if you've got a modern GPU capable of running PhysX (i.e., a recent nVidia card), you'll probably be able to run the game with playable frame rates. 
 
Unfortunately, if, like me, you have a slightly aged ATI card (mine's a 4850 512 MB), then you are going to get some pretty significant hits to performance, below the thirty frame threshold.

Here is the setup I have.  I am running everything on medium to high settings with all of the effects and AA turned on except motion blur (this is just off due to me not usually liking it) and running at 1280x1024.  So yeah, my monitor is still a 5x4 logitech bought in 2005ish and my gaming rig is as follows;
 
AMD64 X2 4600+
Asus A8N Mobo
3 gigs of ram 
nVidia Geforce 9800 GTX+ 
Windows 7
 
...so yeah, this thing is getting pretty long in the tooth, but it is kicking ass for this game, so if you have around the same specs, it runs spectacular. 
 
[EDIT] Oh yeah, I am running windows 7.