I mean really, reading through here, I find reasons to agree with posters on both sides of the argument.
But really, when it comes to building a high-end, performance rig, your CPU is only one cog in a complicated machine. I think a lot of folks focus too much on CPU performance as a yardstick for computer performance.
A high-end CPU with a midrange motherboard, inadequate ram, inferior GPU, or slow drive speeds is going to perform in the midrange.
Conversely, having a rig with a good GPU, plenty of high-speed ram, a decent mobo, and faster drives will do tons to compensate for a lackluster CPU.
Bearing that in mind, you should be able to build a high-end gaming rig around one of the higher-end FX series chips, absolutely... But it's only one component.