$3k is not consensus!
I'm going to echo what some of the others have said in here and say that $6000 is way too much to spend on a gaming PC - heck, ANY PC. But I'm going to take it one step further and say that even $3000 is too much to spend. I wouldn't go above $1500 or $2000.
You hit a point of extreme diminishing return once you hit the $1000 area. I built my PC last year in April of 2008 for $700 (monitor not included) and it will run ANY game you throw at it, including Crysis. For $1500 of today's hardware you could build a gaming PC that will run Crysis at 60 FPS on max detail. There's no need to go above that level of performance - no game would need it. It's just not worth going much past $1500. Pieces of hardware are so cheap and efficient these days that you can get an incredible bargain for not much money.
Lasereth is on vacation, else I would ask him to chime in here.
Here is a chart I've made just for this thread!
