I wouldn't expect Windows support anytime soon, especially Windows containers running in a Linux host using LXC as the "hypervisor".

Windows containers running in a Windows host is much more likely. Commercial solutions like Virtuozzo Containers offer Windows on Windows support today [1]. Someone could implement a Virtuozzo-for-Windows provider for Docker, but that seems like a long shot.

[1]: http://www.parallels.com/products/pvc/what-s-new-for-windows...