I'm happy to backup Dirtydogs claims that this game is all about Quad Core. All I've changed in my machine is my CPU - it was an E4300 @ 3Ghz, now its a Q6600 @ 3Ghz. I've added 17fps to my benchmark score and the game is now utterly playable.
If that's the average then i expect your fps will spend a lot of time in the mid 20's.
Here's mine with a quad (don't take the benchmark too serious though).
Oh ffs, the high post count brigade are ganging up on me.[/QUOTE