This is nothing new. MS has been pushing for subscription based services for a long, long time. The market hasn't been ready for it though. That is slowly changing but we are still a long way from main stream subscription models on a lot of things. For example, it works for Netflix but not for apps (many people are outraged by the thought of anything other than buy once and free updates for life).
The same for music, the subscription model hasn't caught on. The majority would still rather stream on a non-subscription and would rather buy the song and have their licensed copy stored for them in the cloud than buy a streaming subscription. In the end it is the same thing. Times are changing and we can expect to see more of this in the future and there are already early adopters who prefer it.