Skylake/ Kaby Lake or wait for Coffee Lake

Hello there my fellow masterrace brothers and sisters.

I've decided to build a new rig after six years with the good ol' 2500k which i'm running at a healthy 4.5 ghz.

I was thinking of getting a Z270 mobo and 6700k for increased for even more longevity this time around but Intel's announcement at Computex and rumours regarding Coffee Lake got me thinking whether I should wait for the claimed 30% gain and possibly a 6c/12t i7? I know an i7 will not become obsolete overnight but I guess I could wait longer for a few months if it means I could get a 6 core i7 instead of the current quads.

I've already bought a gtx 1070, Corsair Crystal 460x and be quiet's Dark Rock Pro 3. Whatever cpu I end up buying, will be used 5 years minimum, so I'd be willing to wait a few months more if Coffee Lake is coming in Q3-Q4 2017. Longer than that, I'm not that eager to wait. I'm in no way displeased with, the now legendary, 2500K in any way, but z67 chipset is really starting to show its age in terms of features.

So, what do you guys think?

*There's also a significant rebate offer where I live. Asus offers more than 150 dollars if I buy a 6700k and something along the lines of Z270 TUF mk1 or Strix Z270E.