I provided replies to several possible interpretations of fairly vague points you seemed to be trying to make.
As someone who has fairly extensive experience speccing, setting up, maintaining and using both platforms in high-end post production contexts, I simply don't agree with that assessment. At all. I'm not, mind you, talking about support in the sense of vendors taking your phone calls when things go wrong here. I'm talking about support in the sense of things not going wrong in the first place because you're running on the exact hardware the vendor tested. The vastly wider range of hardware in the PC world inevitably undermines this. It's unavoidable. Sure, for some high-end products a vendor might basically tell you "Buy this exact HP workstation, install these exact PCIe cards," but that goes out the window as soon as you're not just buying machines to run a single app.
And, I should point out, people in this thread are doing things like comparing the Mac Pro's price/performance to that of self-built PCs. What we're talking about here is miles from that. "Buy this exact model of HP workstation and install these exact PCIe cards" does get you a lot closer to the sort of consistency you can get in the Mac world (not quite all the way, but closer). However, the new Mac Pro is quite a lot more competitive with HP workstation pricing than with the DIY systems built using gaming components that some folks seem to feel it can be validly compared to.
Frequent updates are not necessarily what one wants in critical contexts. Apple is known to have hired a bunch of AMD engineers earlier this year. It seems unlikely AMD itself is actually entirely uninvolved in the process of creating OS X drivers. And with Apple, you have a single company responsible for the computer, the graphics card, the operating system, the drivers, and even some of the apps, pulling together things done by five different parties on the Wintel side. That sort of integration counts for something.
I was just comparing OS drivers and support for the hardware, be it Windows or OS X. And stating that at the workstation level they are both very well supported, windows is not lacking.
You choosing to take certain software written for OS X, and in this case post production which tends to be dedicated to Mac pros, so you get the benefits of a specialised software, written for dedicated hardware and turn that into an argument that the Mac pro is better supported. Well hell yeah, that is obvious as. You using macs for post production work...... of course your going to think they are amazing. Its like me saying my gaming PC is better at gaming than any mac, with better driver support, better software support etc.... not a relevant argument.
I was talking pro use in general, for software that runs on both windows and macs. I can also take certain software that run alot better on windows and making sweeping statements how windows are much better supported, better performance etc.
If one does a hardware v hardware comparison, the mac pro needs to be compared to Xeon based PC work stations. That gives you the closest comparison.
If you are buying a workstation for professional workflow, you are going to be paying top dollar, be it windows or Apple, cause you are paying for the support and set hardware.
If you want to buy a computer for home, and you care about rendering/video, why exactly should you limit yourself to a workstation, and that is why people compare DIY PCs. They can get higher performance than a mac pro, but at the same time they have to accept that stability will suffer.
While I understand in your specialised world exactly why Mac pros offer the best solution for you, that is exactly why all our post production at work happens on Macs. Though a very specialised world. There is a much bigger world out there, and you cannot make a broad statement that one is supported better then the other, when you choose and pick the applications.
If you smart, you buy yourself a quality Motherboard from say ASUS, purchase ram that is compatible with that motherboard (ASUS has charts), a quality PSU, Quality SSD, and a GPU based on a reference design, hence using Nvidia/AMD stock drivers. You not going to have alot of driver issues with this path. Buy the right hardware and its very well suported at the consumer level, even when you DIY.