I just chose a refurb 15" 2.8/1 TB/M370 ($2719 direct from Apple). I need a computer before October, and I'm not sure the trade offs in the new one are going to appeal to me. I'd like more RAM and SSD than are currently on offer, but none of the rumors even mention whether that's happening.
Skylake alone is a minor upgrade of ~10% in CPU performance - I honestly don't care (the 2.8 gHz Haswell will beat all except the top Skylake).
Polaris has a lot more potential than Skylake (50% GPU performance?), but I don't game and Adobe is historically slow and troubled with GPU support...
I'd like the OLED strip, but I'm not willing to lose ports or accept the MacBook keyboard to get it - it's "nice to have", not "this will change my life".
As long as it's not heavier and doesn't lose battery life (Jony Ive would never let either happen), I don't care about size, weight or battery life - the existing Retina is FINE on those things!
It looks like, in order to get Skylake, Polaris and the OLED strip, Apple very well might want me to accept:
No useful ports (except for plugging dongles into

).
No SD reader (as a photographer, I use that one all the time).
The MacBook keyboard.
If it came with a 4K wide-gamut screen, 2TB of SSD and 32GB of RAM, I might well accept a bagful of dongles as the price(I'd have a harder time accepting the MacBook keyboard), but I'm afraid we might see the same screen, SSD and RAM limits in an even sleeker case with Skylake and Polaris (only one model with dedicated GPU)