Anderton
I just wrote a column for Pro Sound News and researched what's happening with Apple and the Mac Pro. There will supposedly be a line of "pro" iMacs later this year, but this seems to be a reaction to the Surface Studio, and there's some concern that Apple sees "pro" as "prosumer." There's no touch screen or anything like Microsoft's dial. I also don't think any Pro Tools users will be running HDX systems on them, although that's just a hunch.
I've wondered for quite a while why Apple haven't either updated or quietly dropped the current Mac Pro model in the same way they quietly dropped their non-Retina and very expensive Thunderbolt display last year.
It's certainly not a particularly good computer for most studio use, the high end iMacs with a faster i7 cpu and PCI SSDs are far better. Ditto photograph processing and pretty much any job that benefits more from cpu speed than 6, 8 or more physical cores and multiple gpus. I guess once you've called something your "flagship product" it's a bit difficult to abandon it even if it's no longer the optimum thing for the job it does.
As for touch screens, it has been argued by some that there already is an Apple multi-touch screen that works quite well with Macs - it's called an iPad >:-) OK, I'm being a bit tongue in cheek, but a combination of Logic Remote and an Apple force-capable touch pad is pretty effective.
Anderton
New Mac Pros aren't supposed to happen until next year, and details are not forthcoming. Meanwhile, the current generation of Mac Pros is two or three generations behind what's happening with Windows machines. As of today, you can spend a lot less for a Windows machine that does a lot more.
Yes, the SONAR Alpha will be released soon...but it will be released into an environment where some pro audio people are really starting to wonder if their future involves a switch to Windows.
I think that's been the case for a few years, maybe prompted as much as anything by the state of software in the semi-pro/amateur DAW market where PCs are common because they're used for lots of other things like graphically intensive games etc. as well. Most people simply can't afford to own multiple computers of any kind, and if you're a gamer Windows wins hands down simply because the vast majority of games are Windows-only.
To my mind, other than gaming, it boils down partly to which operating system you prefer and are used to, partly budget and partly the different total computing environments MS and Apple have adopted. Apple have a huge advantage over MS in the tablets/phones market and iOS integrates with Macs very well indeed. So there's a "compete package" approach that's harder to replicate using Windows. Though that may be a stronger factor outside the peculiarities of the dedicated pro-audio market of course.
A Unix-style system still has advantages in a multi-user environment, and the accounts of problems created by the very frequent Win10 updates that appear on this and many other forums are hardly an advert for MS. Apple tend to only issue an update that breaks some hardware driver models once a year....