I think that there will still be a need for virtualization services. However, these services may not be focused on just the installation and administration of VMware because ESX 3i will be shipping preloaded on servers -- that is approaching plug-and-play. Companies may still need help identifying suitable targets for virtualization and putting together the right holistic infrastructure, including storage and networking.
There is also the political side of virtualization. In the past, each department might own a physical server. This is no longer possible when these systems are virtualized. The VAR might want to create a team focused on business consulting to help companies with the transition to virtualization. The IT staff at the company, as well as the business managers, need to be on the same page before moving forward with a virtualization project.
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