Intel is about to roll out its next reaction to Ryzen, with the upcoming Coffee Lake-S architecture and the 'new' Z370 chipset with a butt load of new Z370-based motherboards from the usual companies like ASRock, GIGABYTE, ASUS, MSI, and others.
But, one of the more interesting things to note here is that there will be some gates up when it comes to CPU compatibility between the sockets. If you have a Kaby Lake CPU right now and want to upgrade to a new Z370 board, for whatever reason, you simply can't - even though they are the same LGA 1151 socket.
Hardware.info has found that the new Z370 boards won't work with current-gen Kaby Lake CPUs, and it works the other way around yet, either. So if you run out and buy the upcoming Core i7-8700K, it won't work in your current-gen Z170/Z270 motherboard... but this should work after a BIOS update in the near future, hopefully.