A two-horse race. That's how the market for general purpose desktop virtualization packages is shaping up, at least for the foreseeable future. With Microsoft all but abandoning Virtual PC (no updates in more than a year), and with everyone else focusing on the datacenter (including Microsoft), the field now consists of just VMware Workstation and Sun Microsystems' xVM VirtualBox. And in keeping with many such situations -- where a single product dominates the high end and everyone else tries to find a viable niche -- the two players couldn't be more dissimilar.

In Lane One you have VMware Workstation, the pedigreed blue-blood of desktop virtualization solutions. If there is a bell or whistle VMware missed, I can't spot it. It truly is the pinnacle of "kitchen sink" engineering. In Lane Two you find Sun xVM VirtualBox, a product Sun acquired from tiny innotek earlier this year. VirtualBox's primary claim to fame is that it's free (both as a closed-source downloadable and a more limited open-source exploitable), and this has made it the choice of anti-establishment types who balk at Workstation's retail price tag.

So, the stadium is set. The track is prepared. It's the muscular thoroughbred vs. the scrappy Ol' Paint. And with Sun pouring its vast engineering resources into VirtualBox (for example, it just gained 64-bit guest OS support), the real race may be to see whether VMware can continue to differentiate Workstation at the high-end while VirtualBox slowly eats its lunch among less discriminating customers. It should be an interesting race. And they're off!

Legendary thoroughbred

What is there left to say about VMware Workstation? Few products have spent as much time at the top of the heap. But as I mentioned in my preview of the Workstation 6.5 Beta earlier this year, the company simply refuses to sit on its laurels. With each new major release, VMware raises the bar for would-be competitors. And not just by a few inches -- in the case of version 6.5, think several feet. The change log is that impressive.

But where to begin? I suppose I could talk about my favorite new feature, Easy Install. Simply create a new VM, point it to the installation media for the desired Windows OS edition (client or server), and grab a cup of coffee. By the time you return, VMware has installed the OS (including specifying product keys and default user accounts), slipstreamed its own VMware Tools suite, and basically left you with a fully-baked guest OS image that's ready for work. If you spend a lot of time building and tearing down VMs like I do, you will instantly fall in love with Easy Install.

Direct3D acceleration is another great feature. When enabled, it allows applications in the guest OS to render Direct3D objects with nearly native performance, allowing even demanding programs like DirectX-based games to run within a VM. I've personally used this feature to resurrect some of my old favorites -- games such as Starfleet Command 3 -- that refuse to run natively on Windows Vista. And, of course, any line-of-business applications that use Direct3D will also reap benefits.