Edit:
If we are trying to future proof then I need to know the rest of the parts he plans on purchasing. But yes I can agree that the 2500k will allow more upgrade room in the future.
The rest of the parts will be:
RAM:G.SKILL Ripjaws Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory
HDD:Western Digital Caviar Black 1TB 7200RPM
SSD:Corsair Force Series 3 CSSD-F60GB3A-BK 2.5" 60GB SATA III Internal Solid State Drive
Case:Cooler Master HAF 912 (I'm going to add 2 200mm fans later on)
Motherboard(For the 2500K):ASRock P67 PRO3 SE LGA 1155 Intel P67 SATA 6Gb/s USB 3.0 ATX Intel
CPU Cooler: Cooler Master Hyper 212 +/EVO (I Haven't decided yet).
Also, I will be playing mostly graphically-intensive games such as Battlefield 3, Skyrim, etc.