Are you interested in reading about some of the organisations out there who've bitten the bullet and gone ahead and deployed Windows Server 2008 in production?

Well, there's a list of them right here: https://www.microsoft.com/windowsserver2008/en/us/case-studies.aspx

There are quite a few case studies that mention NAP, or Network Access Protection, with one highlighting "After an initial deployment, help-desk call volume decreased by 75 percent, for a projected annual savings of more than U.S.$150,000 in maintenance costs"

Nice!

There are even more case studies here: http://www.microsoft.com/casestudies/search.aspx?ProTaxID=3243