Microsoft's Kindler, Gentler DRM
PlayReady has some interesting features that might make the DRM pill an easier swallow. As well as being able to handle any type of file type, restrictions are based around the idea of domains: you sign up for a subscription service with someone such as MusicStation, and that subscription defines how many devices you may have in your "domain". Each of those devices is registered with MusicStation and media can be copied freely between them. If you buy a new device you just add it to your domain (by informing MusicStation, and perhaps removing one of your other devices), and all your media will play back on the new device.
What's interesting is that the new device only has to be told it can play back media registered to that domain, and the media can then be loaded using any mechanism (SD Card, Blueooth, etc.) and will play back without recourse to the MusicStation servers - or anywhere else - for permission.
It's Microsoft's version of Apple's FairPlay DRM, which you can get any Apple user to swear isn't DRM as well. The cross-device usability of Microsoft's version is interesting, and might eventually allow the DRM - oops, I mean media content protocol-- to morph onto all sorts of different playback machines, both handheld and set-top.