The same, really. No game will fully utilize either one.

i7 2600k is a better investment right now though, it's new, faster, and overclocks better.

The 960, however, has a slightly more feature rich motherboard - namely with regards to PCIe lanes. If you're thinking of tri or quad GPU setups you basically have to go with X58. Although some P67 boards have the NF200 chip which helps bring it up to par with X58 (but they cost $300).
 
but for most dual SLI and Crossfire is plenty, and will provide more than enough power for the future:
http://www.newegg.com/Product/Product.aspx?Item=N82E16813130583
if your not planning on SLI/crossfire you can opt for a cheaper P67 board: (stilll a very good board with USB3 and SATA3)
http://www.newegg.com/Product/Product.aspx?Item=N82E16813135279

Yeah... which is why I said TRI or QUAD card set ups.