With a test so reliant upon clock speed rather than taking advantage of all the bells and whistles, it's not a great surprise to see that the i7-4770K is a bit better than its brethren, but not stunningly so. However, the new AES tricks definitely have a benefit far greater than the mere 200MHz clock speed difference would bring.
Memory is a lot better on the 4th Generation CPU, despite using the exact same kit at the same 1333MHz speed on both systems. We've added the i7-3930K to the graph just to further demonstrate that the X79 Quad-Channel idea ended up with no real performance benefits.