DoD approved for more than a year:
http://iase.disa.mil/stigs/os/windows/win8.html
http://www.ocio.usda.gov/products-services/end-user-services...
In the case of the IRS, they are _still_ using windows XP, and they are paying Microsoft for support!
http://www.engadget.com/2014/04/13/irs-pays-microsoft-for-wi...
DoD approved for more than a year:
http://iase.disa.mil/stigs/os/windows/win8.html