Kaby desktop is shipping to OEM's now, Kaby mobile is out and Polaris is here..
I could see an iMac and MM fairly early next year but the Mac Pro is probably on hold until Vega so Juneish
Processors weren't really a problem in the iMac. You could always get the top-of-the-line Intel chips in the iMac. For example... i7-4790K and i7-6700K... both quad-core 8-thread CPUs that made the iMac a beast.
The Mac Mini, however, suffered in its last iteration. The loss of quad-core was troubling... and then it sat idle for another two years. I don't really know where it goes from here.
The Mac Pro and its reliance on Xeon processors and ECC memory puts it into a completely different space. People wanted a powerful computer... but they didn't really need "server-grade" components. And I don't really know where it goes either. (the 1,000+ days without an update might be a big clue...)
CPUs are getting (slightly) better all the time. So I hope Apple keeps selecting good CPUs for its desktops... whatever that product line ends up being.
The GPU is where the biggest issues arise in Apple's desktops. I wish Apple could put a "desktop-grade" GPU in the iMac. And they probably could if it didn't remain so thin.
Or maybe finally offer a "headless" Mac.
Look at what ASUS was able to do: an i7-6700K and a full desktop GTX 1080 in a relatively small case. It's small, quiet
and cool for less than $2,000. Add a good monitor and it still costs less than the Mac Pro by itself.
Oh it's ugly as sin... but who sits and looks at their computer that much?
According to PassMark benchmarks... i7-6700K scores 11074 which is higher than the score of 9474 in the Mac Pro's almost 4 year-old processor.
And we already know that the GTX 1080 is a beast. ASUS proved that small
and powerful can coexist.
But after typing all this... I can honestly envision Apple's future line of desktops where the Mac Mini and Mac Pro are gone... and a new "iMac Pro" is released in addition to the normal iMac.
Oh it'll be "pro" in name... but it will still have strange tradeoffs like
mobile GPUs and other nonsense.