The amount of WMA playback capable devices is IMHO quite equal to the ones that support AAC, but even both numbers put together are still much smaller than the number of devices supporting MP3, so it's often inconvenient. But that wasn't my point - I was only trying to say that while this kind of a default setting deserves a slightly negative response, you shouldn't base the whole argument on it, because it's very easy to change and it's not something that's set in concrete so that it could be interpreted as something Microsoft wants to force you with. It's just a bit newbie-unfriendly.
If I use my iTunes argument again - the default format could be MP3 so that it would work on the largest amount of devices by default, but since it's really easy to change, most people don't really criticise it.
Microsoft only implements the support for DRM in Windows. Apple does the exact same thing, HDCP included, but they aren't the ones actually enforcing the DRM. They add the support to their operating systems, because it's needed for certain features. You need to be able to play WMA/AAC files with DRM, because it's difficult to convince record companies to sell you their music digitally in unprotected formats. You need a HDCP-capable graphics card, OS and monitor to play Blu-ray movies. Why isn't ANYONE saying "Evil Samsung, they're forcing us with DRM because their monitors have HDCP support"? By implementing DRM in the OS, Microsoft enables companies that sell content to control you, they don't control you themselves. If you buy your movies and music in online stores that sell files without DRM, Microsoft's DRM support won't kick in and you won't be limited in any way.
The second part of your post is an entirely different issue. You don't actually own OS X either, you just bought a certain license that lets you use it in certain ways. It's the same with most other software, music, movies, etc. Do you expect them to allow you to copy your OS, install it on numerous machines, disassemble it and such? That's silly...
I absolutely agree with you here. Don't think I'm a DRM supporter. I think it's a terrible concept and I'm very happy if things are being done in the direction of removing it. I am only arguing because some people are claiming Microsoft is the most evil link in the DRM chain and practically the inventor and enforcer of DRM. The real bad guys are the record labels - if they reach an agreement amongst themselves, Apple and Microsoft can either implement what they request or tell their users they won't be able to play Blu-ray movies and music from major record labels.
You and me both, brother!