No you don't need anything, both operate of the 1155 configuration. What you may need to do is ask yourself why you be so silly to buy a 2600K with IvyBridge coming soon *bemused.jpg*
Why are you spending money on such a tiny upgrade, you could just go into the BIOS and increase the frequency to that of the 2600k easily. The only reason would be if you are using heavily threaded apps.
Dont know for the OP, but i would gain from the extra 4 threads... all depends what you do with computer... video encoding/rendering benefits from the hyperthreading of the i7