Ryzen R7 has already proven Intel X99 to be overpriced for what it is. Ryzen R3/R5 is about to make those Intel i3/i5's a difficult purchase prospect.
That leaves the 7700K to carry the flag for Intel until Coffee Lake.
Finally after many years, AMD are starting to show just how greedy Intel have been with their inflated pricing on their products. Just need VEGA to deliver the goods and we can start pressuring Nvidia, although the 1080ti put a large dent in that one lol.
Yes X99 has quad channel and more PCI-E lanes, but when an R7 1700 + GTX1080ti can be had for the same price as a 6900k CPU alone it's hard to justify the X99 platform as a Productivity/gaming combo.
How far away is Skylake-E? Would be funny if the new 8/10 core CPU's launched at half their current lineup pricing.