Having looked, I can't find any link citing that one way or the other, but that doesn't change the fact that enough things these days do adhere to semantic versioning that many people expect certain things based on the version number.
node.js decided uses very non-semantic versioning. It's genarally understood that a 0.x release isn't production-ready, but node.js is widely considered production-ready and in fact every even-numbered release below 1.0 is considered stable. That's a pretty arbitrary and nonsensical scheme if you ask me, but you're not. The bottom line is that backwards incompatible changes aren't expected for a 0.x.y release where x is even.
