An overclocked i5-2500k is the best you can get for gaming at this time. (yes there's the massive 6 core Sandy Bridges and the 2600k with hyperthreading, but those don't really show much more than measurable benefit due to games really only benefiting significantly from <=4 threads.
If this CPU doesn't last you 2-3 years, no CPU will. You'll be fine.
Still using my Q9550. Overclocked to 4ghz and it still doesn't significantly bottleneck any single gpu out there. (and it was released in 2008 =P) Nor does it feel the hurt from any CPU-heavy games. Blame consoles for the slowed graphical innovation increase in games.
http://www.asrock.com/mb/overview.asp?Model=P67%20Pro3
"ASRock Extreme Tuning Utility (AXTU) is an all-in-one software to fine-tune different features in an user-friendly interface, which includes Hardware Monitor, Fan Control, Overclocking, OC DNA and IES. In Hardware Monitor, it shows the major readings of your system. In Fan Control, it shows the fan speed and temperature for you to adjust. In Overclocking, you are allowed to adjust the CPU frequency, ratio and some voltages for optimal system performance. In OC DNA, you can save your OC settings as a profile and share with your friends. Your friends then can load the OC profile to their own system to get the same OC settings. In IES (Intelligent Energy Saver), the voltage regulator can reduce the number of output phases to improve efficiency when the CPU cores are idle without sacrificing computing performance."
http://www.asrock.com/mb/cpu.asp?Model=P67%20Pro3