I literally have no idea where you're pulling this 20% figure from.
It looks like hardly improvement at all. Certainly not worth upgrading to from any Intel chip in the past few gens.
Massive disappointment if these bench's are legit, more of the same. Virtually no performance increase, lower power consumption and better integrated graphics. This is a big yawn fest. Nothing exciting coming anytime soon..
At least this makes X99 + 5820K look such a better deal, soldered, 6 / 12 core thread. Massive OC headroom from stock and quad channel memory, no wasted space on poor integrated graphics.
For those that don't run DGPU, and are building into very small case Skylake would be nice, for everyone else their better off with X99. Really is worth the investment over the mainstream stuff. Especially as prices are virtually the same for 5820K + 16GB DDR4 as they are 4790K + 16GB DDR3.
I really AMD sort themselves out and start competing. Intel can just coast along atm...
Meh.