Going to be putting this together soon, hoping for about 3~4 years.
Intel® Core™ i7-2600K Processor (4x 3.40GHz/8MB L3 Cache) OC to 4.0GHz
8 GB [4 GB X2] DDR3-1600 (I can always put 8 more GB in for 16GB total)
NVIDIA GeForce GTX 570 - 1.2GB (may upgrade to GTX 590 in a year)
ASUS P8Z68-V LX
800 watt supply
This setup should keep you running games at high quality for a while. Might want to consider waiting for the newest batch of nVidia GFX coming soon instead of a 590, when you compare 590 to the new AMD7970. Think you might be able to drop the 2600K and go for the 2500K, almost the same, only difference is 0.1 Ghz on stock clock, multithreading and the price.