The Windows ADK for Windows 10 is now available at https://msdn.microsoft.com/en-us/windows/hardware/dn913721.aspx#deploy. (The page also includes other Windows kits; remember for deployment you only need the Windows ADK for Windows 10.)
The MDT product team is working hard to finalize MDT 2013 Update 1, and currently plan on releasing it in August. We know how excited and eager you are to start using MDT for Windows 10 deployments so are doing what we can to signoff this release as quickly as possible.
-- Aaron Czechowski, Senior Program Manager
This posting is provided "AS IS" with no warranties and confers no rights.