[kriss9]

You're taking the marketing approach as opposed to coming up with real solutions -- think critically about the business need, investigate the cost savings and make a transition plan for those who actually add value to the organization.

1) Consider if your organization has a future strategic value for having the org capability in house (is this datacenter simply a necessary evil or does your organization deploy new technologies to new locations for any part of its business)?

If so, you may be outsourcing a core part of your organization's capability (consider it). If not (e.g. these are all simply HR and other general business systems [ or services which do not depend on anything physical], you should proceed to evaluating costs

2) By the thought that you would outsource the majority of jobs means that you probably shouldn't have had the employees in the first place (in the Fortune 50 I know, we mostly used contractors with a quarter dozen employees). Hence I would evaluate if there are other business units which might benefit from their skill (power related, analyst related et al) and offer training per the previous notes.

A good decision to be a part of and my hope is that your answers here inspire the right questions (to allow for the right transition plan for your organization and company as a whole).