The number of PowerShell commandlets (cmdlets) has increased dramatically in Windows Server 2012, and extend to managing Active Directory Clients. You can have GUI, or you can script, or both, we found. What's lacking is a rudimentary filing or document control mechanism to store and identify PowerShell scripts in a way above implying the function of a script by its file name. The power of PS scripting begs a method to readily identify its use without examining its contents thoroughly.
We like that it's syntactically coherent, where Unix/Linux/-alike bash/bourne/-other shell script syntaxes require making "man -k" your best friend as the scripting languages and Linux command's power is often hobbled by their vast historical inconsistencies. Veteran Unix/Linux admins will adapt easily to PowerShell's increased functionality, if they can overcome ideological barriers in using a closed-source, non-free host operating system.
Using Windows Server 2012 in a virtualized environment also has improved. The changes in Microsoft's bare metal hypervisor, Hyper-V 3, now allows an onboard L2/L3 switch to be configured to manage traffic. We tested the hypervisor and VM instances primarily on an HP DL380 G8 Server containing four processor sockets, and 16 cores -- but two licenses in Microsoft's ciphering.
Although the HP was plentifully powerful, in our testing, we didn't have the density needed to test high-traffic, multi-tenant configurations. The switch is programmable and can be enlightened to accommodate VM machine moves among server hosts for host-resource matching.
The infrastructure support in Hyper-V (licensing permitting) is vastly larger in 2012 Server editions compared to 2008R2. We could have 320 logical processors compared with 64 in 2008R2. Physical memory can be 4TB rather than 1TB. Hyper-V3 can support 2,048 vCPUs per host rather than the 512 in Windows 2008R2. The memory per VM goes from the former limit of 64GB to 1024GB. Clusters can grow from 16 nodes to 64 nodes max, in Windows 2012 Server, and the maximum number of VMs jumps from 1,000 to 8,000 in a cluster -- each with guest non-uniform memory access (NUMA, for speed).
But are the VM payloads as slim, lithe, and handy as ginning up bunches of Linux instances? We sought to test how this might work, as licensing issues have dogged rapid deployments of Windows instances into Platform-as-a-Service instances.