From everything I've read it wasn't intended to be specifically for touch and Google's use of it for the new Inbox interface would seem to bear this out.

I use it regularly on a desktop in the context of Google Play Music, and it works great there. I'm looking forward to see where this goes.

From what I've seen of Material it's also a lot about classifying information visually and that's definitely something where desktop OS interfaces can be improved. Nobody likes looking at a jumbled mess of information spread on a flat plane without any general cue as to where you're supposed to look first.