Microsoft is so desperate to move copies of it’s turd Windows 8(by extension Server 2012 and office 2013) it’s now forcing partners to that OS.  I have 1..1 client that actually tolerates Windows 8.  Every other client is avoiding it like the plague that it is.  So basically unless you HAVE to run windows(like for Microsoft SQL) future clients eventually won’t be getting windows servers…it’ll be Linux.  Especially since Linux can now not only do domain/file/dns/and dhcp they can also do group policy as well.  With that capability other than instances there’s no need for a windows server anymore.