His post said something about $50. But also, Sata 6gb/s and USB 3.0 doesn't require the IB chip to work. It works with SB, all that IB does thats a bonus is give PCI-E 3.0 over 2.0, which all in all, is only a 2 percent FPS gain, not worth the extra heated temps to me in honesty. And look at the benchmarks, not a huge difference between the two.
Also, looked at the benchmarks, its a .60 FPS difference, not even a whole 1 fps difference between the two, with the same exact GPU's tested in extensive benchmarks and games, .60 was the average FPS difference, highest was .73, not even 1 fps yet. Overclocked, the 2500k kills the 3570k as it can hit 5.0 GHz and above as the 3570k maxes at 4.5 GHz and anything above 4.3 causes diminishing returns in that cpu.