The API treadmill definitely happens for non-Microsoft stuff as well. One example I think of is Java XML marshaling libraries, and web frameworks. Java has many of both, in various stages of "hotness" and approaches.

But the difference is in the non-Microsoft world there is no "cathedral model", where a bunch of "high priests" come out every year to command some new form of development that everyone must follow.

In the Java world evolution happens in a distributed ("bazaar") style, where the developer community organically moves to various technologies as time progresses, and these technologies rarely comes from the original sponsor of Java (Sun). It works like natural selection.

That's why we got stuff like the Spring Framework which pretty much eclipses the "cathedral"-competitor EJB. It's more even more true in Python and Ruby communities which have nothing resembling a centralized commercial sponsor.