The undertaking of upgrading is a long and horrific task. I have been working with a company that is doing a complete upgrade of their systems. The company is located in China, and is doing a complete upgrade from Windows 2000/XP, and Windows Server 2000. When done it will cover in the neighborhood of 75,000 computers, along with 28 server arrays located in 27 cities. We have just complete the corporate Server array update from Windows Server 2000 to Windows Server 2008 R2. It will not be until the end of this year before the task is complete.
My primary job is putting together the manuals, first in English then we sit down with the publishers to do the conversion to Chinese. There are ten people working on my staff alone. As to the cost, that is not something that has been quoted to me.