Why bother with desktop virtualization?

The proponents of making proper use of desktop virtualization technology including access virtualization, application virtualization and VDI (the combination of access virtualization and processing virtualization) do their best to make it sound like the best things since pockets. Aren't today's laptops, desktops and handheld devices good enough to get the job done? Some suppliers, after all, will promise the sun and the stars, but in the end only provide the moon.

Some of the benefits they claim include:

• Security - it is much harder for unauthorized individuals to access applications and data when the device in front of them is just an access mechanism rather than actually hosting workloads. The same is said of applications that are streamed or copied down to the local machine on as as-needed basis.
• Manageability - individuals no longer have to be system operators or system administrators. Access points can be managed from afar by people who actually like doing it.
• Performance - applications may actually perform better when working in a virtualized environment for a number of reasons. All of the components of the application are encapsulated and load rapidly. Network-based storage may have better caching and, thus, appear to perform better.
• Compliance - in some markets, regulations require organizations to make sure that data does not remain available on a device after the application processing it completes. If the data was never hosted on the local device, there is little reason to fear that it will suddenly appear after an application terminates. Other regulations require that organizations be able to provide information on who accessed and updated data. This, too, is easier when it is centrally located.
• Agility - configurating and re-configuring access devices is much easier when an installation is merely selecting which golden images are going to be made available to a worker based upon that worker's role, location and the like.
• Consolidaiton - some virtualization technology makes it possible for one physical machine to support the virtual desktops of many individuals. Several blade PC suppliers have presented customer profiles in which 10-15 workers were supported by a single blade computer.

Are there are other reasons these suppliers have used to justify the acquisition of one or more of these technologies? Does your organization have any plans to use this technology?