Yes, we will get an iMac with a display you can swing (rotate) the full 360 degrees. The CPU and GPU (+ PSU) are placed in a small box forming the feed of the display holder.
Oh wait... someone in Redmond already thought of that ;-)
AND IT LOOKS LIKE CRAP.
I'm not sure why anyone needs a 360º monitor. Is the dust behind the monitor in need of something?
It would be adequately pleasant if Apple does NOTHING to the exterior design, but jumps up all qualities and quantities of the inner workings, this next year. Let's face it: the iMac is quite good as it is, in exterior design. Apple needs a new keyboard with backlighting and it needs to upgrade hardware to be current-as-can-be.
A quirky redesign of the package would just be fluff for most iMac users. The iMac could become the MacPro of 2020 and beyond (assuming Apple is dumping the Pro sooner than later, and it would work as a Pro for many people... not all. However, it needs to be kept constantly current with better memory, CPU, GPU, drives, USB/BT/TB, monitors, etc., and most of all it needs a premium OS.
Due to the Intel debacle, Apple will probably go to the Axx chips they make within the next 3 or 4 years. Depending on how they shape that switch, it could be incredible or it could be a joke.