AFAIK AoC will not be optimized for quads. An E8500 will serve you better thanks to the higher clocks. If you overclock, the E8500 will have an even bigger advantage because the Q9300 has a very low multiplier and doesn't overclock that well.
I'll be getting a GTX280 in June in order to play the graphic intense 'AoC'.
ROFL
AoC isnt that graphically intense. Im pushing a good solid 50 fps with a C2D 6300 Conroe @ 3.2 ghz, 2 gigs of Corsair, an EVGA 8800 GTX on a Viewsonic 22" LCD @ 1680x1050 res. All options pretty much tweaked out to the max. Funcom did a good job with their coding and the game runs pretty smoothly. You should have played during closed beta, I still have nightmares.
Before you jump on the Nvidia fanboi wagon though, you may what to take a look at what ATI will be releasing before you make a decision. I have a 680i mobo based system atm and I need to build another PC like yesterday. However, Im in a holding pattern right now because I want to see the next gen hardware before I build. At that point Ill make an educated decision and buy whats best, not because it if says Nvidia on it it must be good right?
Without overclocking, and considering you have enough money, I'd say the Q9450 is your best choice. But the E8400 is good too.
Not sure about the P5Q motherboard. It's a bit weird to get a CrossfireX motherboard with an nVidia card. It makes more sense to me to combine a Crossfire MB (X38 or P45) with an ATI card, or a SLI MB (750i or 780i) with an nVidia card. This way you get the option to add a second card later.
