Is i7 2660k good for gaming??

It is still a great gaming CPU. The point of a K series chip is overclocking, so if you have a good aftermarket cooler on it, overclock it.  

Thanks!! but My rig is an Asus Maximus V formula/thunderfx
i7 2600k @3.4
Corsair Vengeance 32gigs ram
Gtx 660 ti sc but is not oc
550 watt power supply
Heaven benchmark score of @ 1210, is that ok?? playing guild wars in 1080 on high minus vsync has avg fps of 70 but will get as low as 10 sometimes but in 720p it does great on heaven and gw2 am i expecting to much??
Does all of this seem compatibale?

The Intel® Core™ i7-2600K is a great processor for gaming with the only draw back for it being the hyper-threading that isnt used in many games. If you pick up a Cooler Master Hyper 212 Evo it is very easy to reach over 4GHz and even possible to reach over 4.5GHz on some of them.