I think Vista might just be the MS operating system that thrusts Linux into the mainstream as a desktop OS, or puts Macs back into prominence.
Currently, Linux is still too much trouble for most regular users. The only one that gives hope, Ubuntu, is hated by part of the community because it encourages the use of non-GNU and/or closed-source software. However, most users need their nVidia drivers and other stuff that isn't open source. Part of the business with computers is indeed with proprietary software, and if people want to make business with a OS, they don't want any stumbling stone in the way.
And since Microsoft holds Apple stock (and even has made a contract with Novell, the owner of SuSE Linux), no matter how the users decide, Microsoft will remain their companion, one way or the other.
I don't care much about the whole DRM issue, since I don't mind. I have no plans of using HD-DVD in the future, and Windows Media Player has lots of options that can be turned off to prevent snooping around one's media library (Microsoft already has deviated far from their original DRM plans (TCPA) in concession to the users, and I think this will remain). In the end, if people really want to, there'll always be a way to circumvent protection mechanisms.
I'm more worried about the efforts to remove the ability of the normal computer user to develop software for their computer. Microsoft is still a strong bastion against those, since they make money with almost every Windows license sold. And the more software there is, the more people will buy it. The original TCPA plan would've enforced that every program has to be signed, and then who gets a certificate would be in the hands of the CA's. Applications not certified would be untrusted. In XP SP2, Microsoft has shown that they want users to still be able to use untrusted software, and I think the trend will continue in Vista. That's why Vista has both a trusted and an untrusted kernel. Originally, the TCPA plans would've allowed to bar the usage of untrusted software, but Microsoft lays it in the hand of the user. And that's an acceptable decision.
The article in the link you posted is very interesting, but a long read. I will read the rest of it in due time.