Excellent move by NVidia. As the article states the future of computing is heterogeneous and the more open design flows are the easier it is for us to take full advantage of them and of heterogeneous hardware.
Surely it runs on windows & Linux. Mac, I don't know.
Anyway, this is a long-awaited step. I wonder how open this access will be. Typically, nVidia is very careful not to disclose any architectural details about their chips.