The Electronic Frontier Foundation has a series of articles on Microsoft's so called "trusted computing" (MS speak for they don't trust you). There are four articles, all of which illustrate the movement towards a point where you no longer control your PC (link here).
Even when there is no law forcing MS to implement some of these DRM efforts, MS appears set to appease Hollywood by implementing them anyway. Go and read all the articles and think about what it means to you and then decide whether your best interests coincide with Microsoft and Hollywood.