Well, VMM is good at capacity planning and identifying which server has the most capacity if you're going to launch a new VM or take an inventory of what's running already, according to Robert McShinsky, senior systems engineer at Dartmouth Hitchcock Medical Center. Dartmouth is in the middle of a migration from Virtual Server to Hyper-V, and has been using Microsoft virtualization products since 2005.

There's not a lot of functionality there to help control virtual-server sprawl, though, which is a much bigger issue than whether you have to shut down an application before you can move it from one VM to another, he says.

Buying Microsoft also lets you manage both VMware and Microsoft virtual infrastructures from the same set of tools, according to Microsoft COO Kevin Turner, who is also in charge of the company's internal IT.

Yeah, but, VMware doesn't publish APIs that would let anyone else manage ESX natively. So customers who want to manage ESX servers from within Systems Center have to buy VMware's management products first. But if you'd already bought them, why would you use Microsoft's management interface to use them, losing some of your functionality in the process?

Muglia—who didn't get to head up the servers and tools division at Microsoft by conceding that any Microsoft servers or tools suffer in comparison to anyone else's —said Hyper-V "is rock solid technically, performs at the same level as ESX, provides a broader set of management capabilities, including managing VMware in addition to the Microsoft environment. It will [also] be about a third of the price that VMware offers."

You'll have to forgive my nostalgia, but that sounds an awful lot like claims Microsoft made about its products when it was chasing technically superior competitors in the NOS market, the email/collaboration market, the Web browser market, the word processing market, and who knows how many others.

In the mid-'90s, for example, Novell's NetWare was king of the LAN and Microsoft was struggling to catch up with versions of Windows NT Server that had a lot more ambition than capability, in many cases.

NetWare's security was far more solid than NT's, it was faster, its directory could deliver real single-sign-on authentication across a global network, and it could reliably replicate both data and directory information to reduce the risk of disaster in case one server failed. Microsoft made the same claims about NT 3.51 and NT 4, though it took a lot more jury rigging, security patching and manual effort to make it comparable to NetWare in any of those capacities.