OK so there's compilation to native code, but no Win32.

This article http://arstechnica.com/gadgets/2012/06/windows-nt-coming-to-... says explicitly "OpenGL ES, the 3D API used by iOS, won't be included, and so 3D applications will have to be rewritten to use Direct3D."

I think there might actually be a subset of Win32 available (the same subset exposed to Windows 8 Metro style apps, or a further subset of that subset), they've not made any of this clear yet though.

You are right that the lack of OGLES support will probably continue to be off-putting to many mobile developers.

I'm sympathetic that they don't have all their decisions made yet, but as a developer it's a bit off-putting that they're asking everyone to develop for this platform for which there will be all these new limitations and restrictions but they won't say what they are. It's really difficult to answer basic questions like "do apps for Metro/WP8/WinRT/Windows RT have to be managed code?" Typically the information is provided like "Use Visual Studio 2012 to code in C++, C#, or VB ..."