personally the core 2 quad socket is old and dead. and phenom II provides the same or slightly better performance at the same price point.
i would consider phenom II, core i7 860, core i7 920
depending on ur budget, in addition i think its time to go for quad cores as more games are now using quad cores
if i were to build a new gaming PC with best value the core i7 860 seems to offer best price to performance in my eyes as it still has hyperthreading which could make a big differnce in some applications and runs at a high 2.8 Ghz stock