For just gaming, the fastest C2Ds are a little faster than the Quads. That's for NOW. Quads have a promising future tho! They'll stay strong longer when "Quad optimized" applications will come out.
Plus, retailers like NCIX are selling the Quad for $285 and Free ground shipping for entire order. It might be irrelevent to you cause you live in BC (might be living close to an NCIX branch...). To me, free shipping for entire order is money in my pocket, me living down east...
But I personally would build around a Q6600 (overclocked of course).