Earlier quoted context omitted.
It's marketing speak, and no one of importance to Microsoft is going to call them on it. I would imagine their line of thinking would be Ubuntu doesn't ship on tablets or phones. OSX doesn't ship on tablets or phones. What they run are stripped down and re-imagined versions of the parent OS. Approval of the magnitude of this claim is up to the reader.
Still, Linux runs on just about everything between a 68000 and an IBM mainframe. As does NetBSD. I find the propensity to lie disturbing.
I think what Microsoft is getting at is, OSX and Ubuntu don't run the same code on their mobile devices. Windows 8 will. It's marketing, and NetBSD doesn't even cross their mind.