Nope, nothing wrong with your setup - it's just the way it currently is tbh.

Osprey is talking hyperbole, if I'm honest. Your CPU could certainly be clocked to 4GHz with the right cooling. After that you will be getting seriously diminishing returns - so no real point jumping from a 920 to a 2500k/2600k. Your graphics card is one of the best on the market, and will be better yet when SLI/Crossfire are supported.

Memory and HDD will have an effect too, but if you've got 4-6Gb or more memory you should be fine anyways - and HDD has little effect on fps, though will possibly have some effect on stuttering, depending on where the bottleneck/un-optimised code really lies.