Re: Linux in code, not in spirit.
To be honest, payment has never been a contention, Free as in speech, not as in beer.
Ms has been open sourcing* things of late, which is to be welcomed.
* Depends which license they use of course, and whether you consider the license used as truly free. Then of course little key bits are kept closed (key bits which often provide a large percent of the project usefulness, the rest being little more than like junk DNA).
I think we can safely say, Microsoft is using Linux though.