There's a variant of disk pooling available with Server 2012.
Yes indeed. But that puppy is an entirely different breed of tech from what they had in WHS.
I've never done anything with pooling in a Windows server production environment. But I did get some (brief) hands-on with it in a lab setting. Looked impressive. But that's one of those things you need to have up long-term before you can say for real how well it works in contrast to something like tossing VMs back and forth. With that, you have immediate feedback if something isn't what they say it is.
I'd have no problem implementing Microsoft's pooling capabilities however, if I were anyplace that would benefit from it. Microsoft's mainline server technology is rock solid. As good - or better - than anything else that's out there in the situations it's intended for.
I've never encountered any real systemic faults with MS Server. Truth is, with Windows Server, most problems I've run into were caused by either a bad initial setup, or by somebody messing with things they were warned were best left alone.
If you follow the directions (RTFM is particularly appropriate advice when doing up a server) and observe what Microsoft considers to be 'best practices' whenever deploying one of their server products, they really are extremely capable and (mostly) worry free. Windows servers that are correctly provisioned (hardware-wise) and which get set up "by the book," offer years of virtually flawless performance. And with minimal management or maintenance.
One of the reasons I tend to be so hard on Microsoft is because I know what levels of technical excellence they're capable of achieving. So if I'm more critical of what they do than some other companies, it's because I do respect them. And I also expect
more of them because of it.