Let's face it. Microsoft is a business and at any point in the future it might change course if it has economic preasures to do so. It can only keep being "good" as long as it has a stream of money coming in that allows this to happen. So the important thing is how they make npm economically viable. They need to have a good business model. I can only imagine GitHub was economically viable when they bought it, hence they left it run indpendently since it provides a revenue stream.