How have you claimed for multi-game multi-user GRID?

Thanks for the wonderful platform of GRID!

I was wondering after watching a few demo videos and SDK documents, that how will it be possible to build a single OS, Multigame, multiuser instance? The important point is how do you handle keyboard and mouse events? Hooks are the most probable approach, but is even hooking on a single OS allowed for multiple users for KB and Mice?
I have this burning question , and I hope nvidia can answer.
I know that we can launch multiple OS instances for the same sake, but that is not what I am looking for!

Hope to hear a reply!