Are you looking forward to migrate existing apps to Windows 8 and Windows Phone? Here's a good news; Live Windows Games with Unity Event will be live streamed on 9 - 10 April, 2013.
Target audience: Core Unity Developers (Don't register if you haven't developed using Unity before)
Live Stream: https://aka.ms/c9unityt
Also if you are a company out there interested in early adaption program for Unity3D, you'll find this official Unity blog post worth reading, http://blogs.unity3d.com/2013/03/07/unity-4-early-access-for-windows-store-apps/