Desktop virtualization will require careful analysis on a case-by-case basis to determine if it will meet the cost and usability needs of the individual organization. Most organizations who choose to go this route will likely opt to only partially virtualize. Theyll use it only in cases where it makes the most sense, such as roaming users and remote workers, while keeping traditional desktops for many staffers.
Using terminal server options will often be far more common than "true desktop virtualization," which often makes sense only for power users, developers or to support certain applications that work poorly in a terminal server mode.
There is a final usage of virtualization that warrants discussion if only because it is important to understand its use in the business environment. This final type of virtualization is not used to put operating systems into the datacenter on server hardware but instead is used to run additional operating system images on traditional desktops and laptops.
This is a common scenario for people who need to test multiple operating systems for support or development. It is not useful for production systems and is generally outside the scope of this discussion. It is a highly useful use of the technology but it is rather a niche scenario primarily useful for compatibility testing.
In all of this discussion there has been, somewhat conspicuously, no mention of Apple's Mac OSX products. There is a reason for this. Apple does not license Mac OSX so that it may be virtualized on non-Apple hardware. And Apple does not have an enterprise-ready virtualization product ready for its own platform.
The only way to virtualize Mac OSX is to purchase full, additional licenses for each operating system instance, thereby eliminating most of the cost benefits of this approach. You would then need to run it on a host-based virtualization product such as VMWare Fusion or Parallels, which are designed for use on top of a desktop and not as a server-class product.
This is a major gap in the Mac OSX portfolio and one of the ways in which Apple continues to lag behind the rest of the market in capability and in its understanding of its business customers' needs. If Apple were to change its licensing strategy around virtualization, Mac OSX would prove to be an extremely popular and useful operating system to virtualize both from the server and desktop perspective.
Virtualization is a great opportunity to lower cost and raise productivity while reducing risk for businesses of any size and with budgets as low as zero. Many technologies promise important improvements for businesses but most create questionable value while incurring real cost.
In contrast, virtualization brings real, measurable value while often costing nothing and often reducing spending immediately. For many businesses virtualization is the technology that they have always dreamed of and is, in fact, available today.