We announced the much anticipated release of the Microsoft Deployment Toolkit (MDT) 2013 when it was first available on October 18, 2013. Read that here if you missed it: Microsoft Deployment Toolkit (MDT) 2013 Now Available.
MDT 2013 brings operating system deployment support for Windows 8.1 and Windows Server 2012 R2, in addition to supporting more recent OS versions, including Windows 7 and Windows Server 2008 R2. You can find the full support list at the link above.
But, for System Center Configuration Manager admins, there seems to be a bit of confusion around which version of MDT must be used with which specific version of ConfigMgr. That can be cleared up quickly.
If your company is running ConfigMgr 2012 SP1 then you have to use MDT 2012 Update 1.
If your company is running ConfigMgr 2012 R2 then you have to use MDT 2013.