This is excellent news. Part of our jobs as user experience specialists or experience designers has always been convincing other people about the importance of taking the user experience into account.
Now that Microsoft is doing that on a massive scale, we should be delighted. Not only because it takes some work of our shoulders, but mostly because the more people are convinced about the importance of taking the user experience into account, the more work we will get and the more interesting this work will become.
It is true that Microsoft is not the first large company promoting the importance of user experience (see for instance the efforts of Apple and Philips in this area, to name just a few), but Microsoft is such a huge player with such a major impact on the public discourse and the corporate way of thinking, that we can only assume that our field will become totally mainstream in the next few years.