Apple is planning new iMac models for later this year, with the 2018 refresh reportedly including a high-end 5K model, with the new iMac powered by Intel's latest Kaby Lake family of processors.
Apple marketing boss Phil Schiller along with engineering head Craig Federighi have confirmed new iMacs are indeed coming out this year, but they didn't tease any of the internals or the displays Apple would be using. Apple could release a new iMac with a native 5K resolution, while Intel's latest Kaby Lake family of CPUs will surely be on offer - with up to the Core i7-7700K available.
USB-C and Thunderbolt 3 will most likely be the default connectivity, and since Apple has already debuted the TouchBar - something they unveiled on their enthusiast MacBook Pro. The new iMac could feature a TouchBar of some sorts, but I'm sure we'll be filled in with all of the nitty gritty details in the coming months.