The 860 is 95w vs 125w of the 1366. The 860 is clocked at 2.8 vs 2.66 of the 1366. The x8 pcie lanes have proven to be almost insignificant in testing. Triple channel memory hasnt proven to be much difference for gaming.http://www.tomshardware.com/reviews/core-i5-lynnfield,2379-3.html
Edit: as well as hyper boost, as far as upgrade path, who needs a 6 core 700 dollar processor anytime soon?
when faster cards get release in the future the x8 x8 will not be able to hold up, having said that x8 x8 is still good as of today, but not in future, since cards will be 2x as fast and will be bottlenecked by x8 x8.
also it's not 700 dollar processor, it's more like 1000+ USD for 6 core when it's released.
also, i think you meant turbo boost, not "hyper boost"